ENTRY COMPUTER Authors: Oliver Knill: May 2001 Literature: for video stuff: http://www.doom9.org, foldoc +------------------------------------------------------------ | AAC +------------------------------------------------------------ AAC Advanced Audio Coding will be the successor of AC3 audio. It is based on AC3 while adding a number of improvements in various areas. Currently player and hardware support for this upcoming audio format is still very limited. +------------------------------------------------------------ | acrobat +------------------------------------------------------------ acrobat A product from Adobe for manipulating documents stored in the PDF (Portable Document Format). +------------------------------------------------------------ | amd +------------------------------------------------------------ amd Daemon which enables the NFS automount. +------------------------------------------------------------ | AMD +------------------------------------------------------------ AMD Advanced Micro Devices, Chip company. +------------------------------------------------------------ | arpwatch +------------------------------------------------------------ arpwatch Daemon to log and buil a database of Ethernet address/IP address pairings it sees on a LAN interface. +------------------------------------------------------------ | ASCII +------------------------------------------------------------ ASCII American Standard Code for Information Interexchange, an industry standard, which assigns letters, numbers and other characters within the 256 slots available in the 8-bit code. +------------------------------------------------------------ | AC3 +------------------------------------------------------------ AC3 Initially known as Audio Coding 3 AC3 is a synonym for Dolby Digital these days. Dolby Digital is an advanced audio compression technology allowing to encode up to 6 separate channels at bitrates up to 448kbit/s. For more information please check out the Dolby website. +------------------------------------------------------------ | ASF +------------------------------------------------------------ ASF Advanced Streaming Format. Microsoft's answer to Real Media and streaming media in general. +------------------------------------------------------------ | AT +------------------------------------------------------------ AT keyboard The standard keyboard used with the IBM compatible computer. +------------------------------------------------------------ | backdoor +------------------------------------------------------------ A backdoor is a "mechanism surreptitiously introduced into a computer system to facilitate unauthorized access to the system". An example of a backdoor is "bindshell". +------------------------------------------------------------ | AVI +------------------------------------------------------------ AVI Audio Video Interleave. The video format most commonly used on Windows PC's. It defines how video and audio are attached to each other, without specifying a codec. +------------------------------------------------------------ | Bandwidth +------------------------------------------------------------ Bandwidth Bandwidth measures how much information can be carried in a given time period over a wired or wireless communications link. A typical broadband speed is 1270 Kbps (kilo bit per second) which is 155.6 KBytes/sec Technology Speed mbit/s 56k modem 0.056 DSL varies cable varies T1 1.544 Ethernet 10.000 T3 44.736 OC-3 155.520 OC-12 622.080 OC-48 2,488.320 OC-96 4,976.640 OC-192 9,953.280 OC-255 13,219.200 see http://home.cfl.rr.com/cm3/speedtest7.htm http://jetstreamgames.co.nz/speed/ADSLdownload1MB.html http://home.cfl.rr.com/eaa/Bandwidth.htm +------------------------------------------------------------ | BUP file +------------------------------------------------------------ BUP file A bup file is a Back UP file of an IFO file. These files are commonly found on DVDs. +------------------------------------------------------------ | Byte +------------------------------------------------------------ One Byte is an information unit of a sequence of 8 bits. +------------------------------------------------------------ | CASE +------------------------------------------------------------ CASE: Computer Aided Software Engineering. +------------------------------------------------------------ | Cell (ID) +------------------------------------------------------------ Cell (ID) A cell is the smallest video unit on a DVD. Normally used to contain a chapter it can also be used to contain a smaller unit in case of multiangles or seamless branching titles. +------------------------------------------------------------ | certificate +------------------------------------------------------------ A certificate is a digital identifcation of a physical or abstract object, a person, business, computer, program or document. A digital certificate is much like a passport. It is issued by a certificate authority, which vouches for its authenticity. +------------------------------------------------------------ | Codec +------------------------------------------------------------ Codec COder/DECoder. A codec is a piece of software that allows to encode something - usually audio or video - to a specific format and can decode media encoded in this specific format again. Popular Codecs are MPEG1, MPEG2, MPEG-4 (=divx=xvid), realvideo, wmv, dv Indeo, etc. MPEG, AVI, ASF, Quicktime is not a codec but a container format - that can be encoded using different codecs. In avi container files, there's mostly mpeg4 video content and mp3 audio content but this is not obligatory. For DVD, the video should be in mpg2, the audio in mp2 and both of these will be in a mpeg-ps (program stream aka "vob") container. +------------------------------------------------------------ | Container +------------------------------------------------------------ Container A container is, like the name says, a construct to contain data - in this case video and audio date and possibly subtitles and navigational information. For instance, you would like to put a soundless video stream and the audio track together in one file. To do that you need a container format. Examples of container formats are: AVI, ASF, OGM, Quicktime, VOB and MPG. In avi container files, there's mostly mpeg4 video content and mp3 audio content but this is not obligatory. For DVD, the video should be in mpg2, the audio in mp2 and both of these will be in a mpeg-ps (program stream aka "vob") container. % A cookie is a block of information recorded and stored within the client's browser. +------------------------------------------------------------ | CSS +------------------------------------------------------------ CSS Cascading Style Sheets is a simple mechanism for adding style (e.g. fonts, colors, spacing) to Web documents. For example: body, table font-family: verdana, arial, geneva, sans-serif; +------------------------------------------------------------ | CSS +------------------------------------------------------------ CSS Content Scrambling System. Prioprietary scrambling system for video DVDs. Designed to stop people from making copies of DVDs, most commercial DVDs are encrypted using CSS. During playback, DVDs are then decrypted on the fly. Only parts of the DVD are encrypted (for instance all IFO and BUP files are not encrypted, and VIDEOTS.VOB often isn't encrypted either) and the encryption scheme is rather weak and was quickly defeated. If you want to know what CSS does, insert a DVD video disc into your PC, start playing the disc using a software DVD player, then close the player. Now copy a 0.99GB VOB file from the disc to your harddisk and try to play back that VOB file in your software DVD player. You'll see a lot of funny colored blocks all over the picture making the movie unwatchable. But you'll also see parts of the movie (the parts that are not encrypted). +------------------------------------------------------------ | DAR +------------------------------------------------------------ DAR Display Aspect Ratio. Indicates the dimension of a screen. Most PC screens have a DAR of 4:3, meaning that the horizontal size is 4/3 as large as the vertical size. For TVs we have a lot of old 4:3 displays and more and more 16:9 displays. As you can guess from the numbers 16:9 displays are broader than 4:3 displays having the same diagonal size. 16:9 screens are more suited to display Hollywood movies which are usually shot with an aspect ratio of 1:2.35 or 1:1.85 (meaning that the horizontal size of the picture is 1.85 times as wide as the vertical size). +------------------------------------------------------------ | Deinterlace +------------------------------------------------------------ Deinterlace The process of restoring a progressive video stream out of an interlaced one is called deinterlacing. +------------------------------------------------------------ | Demultiplexing +------------------------------------------------------------ Demultiplexing The opposite of multiplexing. In this process a combined audio/video stream will be separated into the number of streams it consists of (a video stream, at least one audio stream and a navigational stream). Every VOB encoder demultiplexes the VOB files before encoding (FlaskMpeg, mpeg2avi, dvd2mpg, ReMpeg2) and every DVD player does the same (audio and video are being treated by different circuits, or decoded by different filters on a PC). +------------------------------------------------------------ | Descrambling +------------------------------------------------------------ Descrambling DVDs are usually CSS scrambled - imagine you decide to give a number to each letter, starting with 1 for a, etc. A sentence would become a couple of digits - that's what we call scrambled. Of course CSS is much better than that but it's still quite easy to crack. Descrambling means reversing the scrambling process, rendering our digits to a sentence again, or making our movie playable again - you can try to copy a movie to your hard disk when you've authenticated your DVD drive and play it, you'll get a garbled picture because it's still scrambled. Common CSS descramblers either use a pool of known descrambling keys (DeCSS or DODSrip - they contain a large number of keys but not all of them) or try to derive the key by a cryptographic attack (VobDec - that's why it works on most disc since it's not dependent on a pool of discs). +------------------------------------------------------------ | Digital Video +------------------------------------------------------------ Digital Video Digital video is usually compressed. Since standard loss less compression is insufficient for video, the video codecs have to get rid of unimportant information - stuff the human eye won't see or is unlikely to see. Since that is still not enough modern compression algorithms use keyframes, I and P frames in order to save space. +------------------------------------------------------------ | DivX +------------------------------------------------------------ DivX There are 2 flavors of DivX today: DivX is the name of the hacked Microsoft MPEG4 codecs (Windows Media Video V3). Those codecs were developed by Microsoft for use in its proprietary Windows Media architecture and initially supported encoding AVIs and ASFs but all non-beta versions included an AVI lock, making it impossible to use them to encode to the AVI format - and only a few tools support ASF today. What the makers of DivX did is remove that AVI lock making it possible to encode to AVI again, and changed the name to DivX video in order to prevent confusion of codecs, since it's possible to have both the unhacked and hacked codecs on the same computer if you use the Windows Media Encoder. The latest releases of DivX also include a hacked Windows Media Audio Codec called DivX audio - the hack of that codec is not perfect yet and its use is limited for higher bitrates. This codec is also known as DivX3. The other DivX is a brand-new MPEG-4 video codec developed by DivXNetworks. It offers much advanced encoding controls and 2 pass encoding. Furthermore the codec can play the old DivX3 movies. The codec is commonly called DivX4. +------------------------------------------------------------ | DHCPD +------------------------------------------------------------ DHCPD Daemon to service which can dynamically assign IP addresses to its client hosts. +------------------------------------------------------------ | DOM +------------------------------------------------------------ DOM The Document Object Model is a platform- and language-neutral interface that will allow programs and scripts to dynamically access and update the content, structure and style of documents. +------------------------------------------------------------ | DOS +------------------------------------------------------------ DOS is a Disk operating system, based on a command line user interface. MS-DOS 1.0 was released in 1981 for IBM computers. While MS-DOS is not much used by itself today, it still can be accessed from Windows 95, Windows 98 or Windows ME by clicking Start/Run and typing command or CMD in Windows NT, 2000 or XP. +------------------------------------------------------------ | DRC +------------------------------------------------------------ DRC Dynamic Range Compression. AC3 Tracks contain a much larger dynamic range that most audio equipment can handle, therefore most standalone and software DVD player will compress the dynamic range somewhat, according to the actual dynamic range. In layman terms the volume will be augmented dynamically, e.g. explosions won't become louder or only a bit louder, whereas in normal dialogues the volume will be augmented quite a bit. Since your player will do the same this is the way to go to have augmented volume. +------------------------------------------------------------ | DTML +------------------------------------------------------------ DTML document template markup language. +------------------------------------------------------------ | DTP +------------------------------------------------------------ DTP Desktop publishing. +------------------------------------------------------------ | Dynamic HTML +------------------------------------------------------------ Dynamic HTML is a term used by some vendors to describe the combination of HTML, style sheets and scripts that allows documents to be animated. +------------------------------------------------------------ | Elementary Stream (ES) +------------------------------------------------------------ Elementary Stream (ES) An elementary stream is a single (video or audio) stream without container. For instance a basic MPEG-2 video stream (.m2v or .mpv) is an MPEG-2 ES, and on the audio side we have AC3, MP2, etc files that are ES. Most DVD authoring program require ES as input. +------------------------------------------------------------ | EULA +------------------------------------------------------------ EULA End user licence agreement. +------------------------------------------------------------ | FAT +------------------------------------------------------------ FAT File allocation table. Filesystem used by Windows. Example: Windows 95 users rely on the FAT 16, In 1996 Microsoft introduced the FAT 32 file system, which is still very widely used today besides NTFS on the windows platform. +------------------------------------------------------------ | FUD +------------------------------------------------------------ FUD stands for Fear, Uncertainty, Doubt. It is a marketing technique used when a competitor launches a product that is both better than yours and costs less, i.e. your product is no longer competitive. Unable to respond with hard facts, scare-mongering is used via 'gossip channels' to cast a shadow of doubt over the competitors offerings and make people think twice before using it. +------------------------------------------------------------ | GUI +------------------------------------------------------------ GUI - Graphical User Interface; A desktop-like interface usually containing icons, menus and windows. Invented by Xerox, later "borrowed" by Microsoft and Apple. +------------------------------------------------------------ | HTML +------------------------------------------------------------ HTML Hypertext markup language. Will be replaced by XHTML, and XHTML 2.0 in particular. +------------------------------------------------------------ | HTTP +------------------------------------------------------------ HTTP Hypertext Transfer Protocol. +------------------------------------------------------------ | HTTPD +------------------------------------------------------------ HTTPD Daemon to Apache webserver. +------------------------------------------------------------ | Hypertext +------------------------------------------------------------ Hypertext - shortcuts or links between different parts of a document, article, website or world wide web. While early hypertext formats were already Apples Hypercard, it is now common in HTML (Hypertext markup language). +------------------------------------------------------------ | inetd +------------------------------------------------------------ inetd Daemon which is at the heart of providing network services like telnet or ftp. +------------------------------------------------------------ | IFO file +------------------------------------------------------------ IFO file InFOrmation file commonly found on DVDs. Such files contain navigational information for DVD players. +------------------------------------------------------------ | Interlaced +------------------------------------------------------------ Interlaced Interlaced is a video storage mode. An interlaced video stream doesn't contain frames but fields with each field containing either even or odd lines of one frame. +------------------------------------------------------------ | IP +------------------------------------------------------------ IP Internet Protocol. Standard which defines the structure of a message sent between two computers over the network. +------------------------------------------------------------ | IPFW +------------------------------------------------------------ IPFW IP firewall. +------------------------------------------------------------ | ICMP +------------------------------------------------------------ ICMP Internet Control Message Protocol. ICMP messages contain information about communication between two computers. +------------------------------------------------------------ | Java +------------------------------------------------------------ Java is a true compiler-based, low level programming language. % Javascript is a scripting programming language. It was developed by Netscape and used to create interactive Web sites. JavaScript is a popular client-side scripting language because it is supported by virtually all browsers. +------------------------------------------------------------ | KISS +------------------------------------------------------------ KISS - Keep It Simple Stupid. Rule of thumb for software designers. Keep design small to minimize confusion. +------------------------------------------------------------ | LDAP +------------------------------------------------------------ LDAP Lightweight Directory Access Protocol. A network directory which can substitute DNS and much more. Not to be confused with a database. A directory is mostly looked up and not written often into. +------------------------------------------------------------ | LDIF +------------------------------------------------------------ LDIF LDAP interchange Format is a standard text file for storing LDAP configuration information and directory contents. +------------------------------------------------------------ | MathML +------------------------------------------------------------ MathML is a low-level specification for describing mathematics as a basis for machine to machine communication. It provides a foundation for the inclusion of mathematical expressions in Web pages. +------------------------------------------------------------ | miniDVD +------------------------------------------------------------ miniDVD Basically a DVD on a CD. A miniDVD can contain bitrates up to 10mbit/s (audio and video combined). Video is MPEG2, preferably VBR and audio can be MPEG1 audio layer 2, raw uncompressed PCM or AC3. Video quality can be up to an actual DVD level if a limited playtime is accpted. +------------------------------------------------------------ | MPEG +------------------------------------------------------------ MPEG MPEG means Motion Picture Expert Group and it's the resource for video formats in general. This group defines standards in digital video, among it the MPEG1 standard (used in Video CDs), the MPEG2 standard (used on DVDs and SVCDs), the MPEG4 standard and several audio standards - among them MP3 and AAC. Files containing MPEG-1 or MPEG-2 video often use either the .mpg or .mpeg extension. +------------------------------------------------------------ | MPEG4 +------------------------------------------------------------ MPEG4 Is pretty much a collection of standards defined by the MPEG Group, and it should become the next standard in digital video. MPEG4 allows the use of different encoding methods, for instance a keyframe can be encoded using ICT or Wavelets resulting in different output qualities. +------------------------------------------------------------ | MPG +------------------------------------------------------------ MPG MPG can be either an abbreviation for MPEG or is used as a file extension for MPEG-1 and MPEG-2 video data. It is a container to contain MPEG-1/2 video stream and MPEG1 layer 2 audio (aka mp2 files). MPG containers are also refered to as program streams (PS). +------------------------------------------------------------ | MM4 +------------------------------------------------------------ MM4 Multiple MPEG 4: A combination of different bitrate encoded files. For instance you could take a 2000kbit/s encode, a 910kbit/s encode and combine the files together, use the lower bitrate file and replace scenes where the quality gets too bad due to a lot of action with the parts taken from the 2000kbit/s one. +------------------------------------------------------------ | NAT +------------------------------------------------------------ NAT Network Address translation. A typical home user with broadband access and router performs Network Address Translation, or NAT allowing multiple computers to share a single fast Internet connection. +------------------------------------------------------------ | .Net +------------------------------------------------------------ .Net A collectionof technologies pushed by Microsoft. It contains C# programming language (an alternative to Java). Part of the .Net initiative. It builds on standards like XML and SOAP. +------------------------------------------------------------ | Network layers +------------------------------------------------------------ Network layers Application layer: Client and server programs. Transport layer: TCP and UDP protocols, service ports Network layer: IP packets, IP addresses, ICMP messsages Data link layer: Ethernet frames and MAC addresses Physical layer: Copper wire, fiberoptic cable, radio +------------------------------------------------------------ | Newbie +------------------------------------------------------------ Newbie - (Also n00b and newb) a newcomer to a certain computer topic or program asking help from experienced user. +------------------------------------------------------------ | NFS +------------------------------------------------------------ NFS Network file system. +------------------------------------------------------------ | OGM +------------------------------------------------------------ OGM OGM stands for OGg Media which is the name of the Ogg container implementation by Tobias Waldvogel. OGM can be used as an alternative to the AVI container and it can contain Ogg Vorbis, MP3 and AC3 audio, all kinds of video formats, chapter information and subtitles. +------------------------------------------------------------ | Perl +------------------------------------------------------------ Perl Perl is a high-level programming language. It derives from the C programming language and to a lesser extent from sed, awk, the Unix shell, and at least a dozen other tools and languages. Perl's process, file, and text manipulation facilities make it particularly well-suited for tasks involving quick prototyping, system utilities, software tools, system management tasks, database access, graphical programming, networking, and world wide web programming. These strengths make it especially popular with system administrators and CGI script authors, but mathematicians, geneticists, journalists, and even managers also use Perl. +------------------------------------------------------------ | PHP +------------------------------------------------------------ PHP PHP is a widely-used general-purpose scripting language that is especially suited for Web development and can be embedded into HTML. +------------------------------------------------------------ | Pocket PC +------------------------------------------------------------ Pocket PC Operating system for handhelds. Usually running Microsoft CE or the Palm OS. +------------------------------------------------------------ | PNG +------------------------------------------------------------ PNG is graphics file format for the lossless, portable, well-compressed storage of raster images. Indexed-color, grayscale, and truecolor images are supported, plus an optional alpha channel for transparency. Sample depths range from 1 to 16 bits per component (up to 48bit images for RGB, or 64bit for RGBA). +------------------------------------------------------------ | Python +------------------------------------------------------------ Python is an interpreted, high-level, object-oriented programming language. +------------------------------------------------------------ | QNX +------------------------------------------------------------ QNX is a realtime, microkernel, preemptive, prioritized, message passing, network distributed, multitasking, multiuser, fault tolerant operating system. +------------------------------------------------------------ | Qt +------------------------------------------------------------ Qt ("kjut") Multi platform toolkit and graphics library. Developed by Trolltech. Runs on Windows systems including XP, all unix derivates with X windows as well as Mac OS X. +------------------------------------------------------------ | PCMCIA +------------------------------------------------------------ PCMCIA Personal Computer Memory Card International Association. +------------------------------------------------------------ | RDBM +------------------------------------------------------------ RDBM relational data base manager. +------------------------------------------------------------ | rff/tff +------------------------------------------------------------ rff/tff RFF means repeat first frame, it's a technique used to make the necessary 29.97 frames per second out of a 24 frames per second source - the movie like it was recorded with a traditional movie camera used by Hollywood. The rff flag tells the player to repeat one field of the video stream. Tff means top field first and is also used to perform a telecine to make a 24fps movie into 29.97fps. +------------------------------------------------------------ | Real time operating systems +------------------------------------------------------------ Real time operating systems Operating systems which are used in handhelds, robots, telphone switches. Examples: QNX, VxWorks (as used in Mars rovers), Windows CE (as used in handhelds), Nucleus RTX. Realtime systems must function reliably in event of failures. It is said that the three most important things in Realtime system design are timing, timing and timing. +------------------------------------------------------------ | Ripping +------------------------------------------------------------ Ripping Ripping means copying a DVD movie to the hard disk of the computer. This includes the authentication process for the DVD Drive and the actual CSS Descrambling. CSS (Content Scrambling System) is a copy protection scheme designed to prevent unauthorized copying of DVD movies, although many argue that it was also designed to control where DVD movies can be played since without a CSS license you essentially have to crack the encryption to play a DVD movie. The term "ripping" is also often used to describe the whole process of descrambling a DVD, then convert the audio and video into another format. +------------------------------------------------------------ | RSS +------------------------------------------------------------ RSS is a method of distributing links to content in a web site so that others can use use it. It's a mechanism to "syndicate" the content. The original RSS, version 0.90, was designed by Netscape as a format for building portals of headlines to mainstream news sites. RSS is an acronym for Really Simple Syndication. +------------------------------------------------------------ | RTFM +------------------------------------------------------------ RTFM - Read the fucking manual. Common answer to basic and often repeated questions, that could be avoided in the first place just by looking at the manual. +------------------------------------------------------------ | RSS +------------------------------------------------------------ Really Simple Syndication RSS is an XML-based format for content distribution. For example, News.com offers several RSS feeds with headlines, descriptions and links back to News.com for the full story. % ROUTER a machine designed to direct packets from their source host to their destination. +------------------------------------------------------------ | RDBMS +------------------------------------------------------------ RDBMS A Relational Database Management System. Stores data related tables. A single database can be spread across several tables unlike flat-file databases where each database is self-contained in a single table. +------------------------------------------------------------ | SBC +------------------------------------------------------------ SBC Smart Bitrate Control. A new kind of DivX encoder called Nandub can modify many internal codec parameters on the fly during compression, giving you better quality and a lot more control over the encoding session. More information can be found in the SBC guide in the DivX guides section. +------------------------------------------------------------ | SGML +------------------------------------------------------------ SGML The standard Generalized Markup Language (SGML) is a meta Markup Languages like XML. They are used for defining markup languages. A markup language defines using SGML or XML has a specific vocabulary. +------------------------------------------------------------ | SMIL +------------------------------------------------------------ SMIL Synchronized Multimedia Integration Language. It enables simple authoring of interactive audiovisual presentations. SMIL is typically used for "rich media"/multimedia presentations which integrate streaming audio and video with images, text or any other media type. SMIL is an easy-to-learn HTML-like language, and many SMIL presentations are written using a simple text-editor. +------------------------------------------------------------ | SOAP +------------------------------------------------------------ SOAP Simple object access protocol. +------------------------------------------------------------ | SQL +------------------------------------------------------------ SQL structured query language. +------------------------------------------------------------ | Sun ONE +------------------------------------------------------------ Sun ONE Sun Open net initiative. Answer to .Net initiative of Microsoft. Has Java, XML and SOAP as foundation. +------------------------------------------------------------ | SVG +------------------------------------------------------------ SVG The Scalable Vector Graphics is a language for describing two-dimensional graphics in XML. SVG allows for three types of graphic objects: vector graphic shapes, images and text. Graphical objects can be grouped, styled, transformed and composited into previously rendered objects. The feature set includes nested transformations, clipping paths, alpha masks, filter effects and template objects. +------------------------------------------------------------ | TCP +------------------------------------------------------------ TCP Transmission control protocol. An IP message type. Most network services run over TCP. A typical TCP connection is visiting a remote web site. +------------------------------------------------------------ | TCPA +------------------------------------------------------------ TCPA (Trusted Computing Platform Architecture) belongs to DRM (Digital rights management). TCPA aims at integrity of kernel and system components - to assure you that your system can be trusted. Palladium, on the other hand, uses similar technology to make sure that the user does not do anything else than what is allowed by content owners. +------------------------------------------------------------ | TLD +------------------------------------------------------------ TLD Top level domain. The last entry in a webaddress. The TLD of www.w3c.org is "org". In the 1980s, seven TLDs (.com, .edu, .gov, .int, .mil, .net, and .org) were created. Later four of the new TLDs (.biz, .info, .name, and .pro) as well as sponsered TLD's .aero, .coop, and .museum) were created. TLDs with two letters (such as .de, .mx, and .jp) have been established for over 240 countries and external territories and are referred to as "country-code" TLD. +------------------------------------------------------------ | UDP +------------------------------------------------------------ UDP User Datagramm Protocol. Sendes transport-level data between two network-based programs. For example, internet-time servers are assigned UDP services. +------------------------------------------------------------ | UML +------------------------------------------------------------ UML Unified modelling language is a language for specifying, visualizing, constructing, and documenting software systems, as well as for business modeling and modeling of other non-software systems. +------------------------------------------------------------ | VCD +------------------------------------------------------------ VCD Video CD, works on many DVD players, there are software players on almost every operating systems, doesn't need a fast computer but the image is VHS-like. Video is MPEG1 at 1150kbit/s and audio MPEG1 audio layer 2 at 224kbit/s. +------------------------------------------------------------ | VLDB +------------------------------------------------------------ VLDB Very large data base. +------------------------------------------------------------ | VML +------------------------------------------------------------ VML Vector Markup Language +------------------------------------------------------------ | W3C +------------------------------------------------------------ W3C The World Wide Web Consortium (W3C) develops interoperable technologies (specifications, guidelines, software, and tools) to lead the Web to its full potential. W3C is a forum for information, commerce, communication, and collective understanding. +------------------------------------------------------------ | Wavelets +------------------------------------------------------------ Wavelets Wavelets are an alternative basis space. There are infinitely many wavelet bases (Daubechies, Haar, Mexican Hat, "Spline", Zebra, etc), but their primary feature is that they are localized. Fourier basis functions span all space (from negative to positive infinity). Wavelets are basically individual pulses of waves (at various positions and scales). Their value in compression stems from factors like the grouping which generally shows that a good 90% of the data is modelled by the low-pass filters, with the high-pass filters generally showing very small values that are mostly details. (of course, this is not true if the source is noisy in the first place). For images, the greatest value comes from localization of the basis, which means that we can model discontinuities (e.g. edges) VERY well with wavelets. You will NOT get those weird JPEG halos if you use wavelets. +------------------------------------------------------------ | WebDAV +------------------------------------------------------------ WebDAV Web-based Distributed Authoring and Versioning. A set of extensions to the HTTP protocol which allows users to collaboratively edit and managa files on remote web servers. +------------------------------------------------------------ | Widget +------------------------------------------------------------ Widget- objects that make up interfaces, i.e. mouse, menus, textbox, buttons; basic tools and objects. +------------------------------------------------------------ | Windows Media +------------------------------------------------------------ Windows Media Microsoft's proprietary architecture for audio and video on the PC. It's based on a collection of codecs which can be used by the WindowsMedia Player to play files encoded in any supported format. WindowsMedia 7.0 offers a new set of codecs, among them a fully ISO compliant MPEG4 codec (called MS Windows Video V1), an improved MPEG-4 codec called MS Video V7 (although I did not notice any improvement compared with MS Windows Video V3 on which DivX is based), an encoder that supports Deinterlacing and Inverse Telecine. +------------------------------------------------------------ | Win FS +------------------------------------------------------------ Win FS Windows Future Storage file system, planned in Windows Longhorn, the successor of Windows XP. +------------------------------------------------------------ | WYSIWYG +------------------------------------------------------------ WYSIWYG- What You See Is What You Get. Usually to distinguish document authoring tools. Writing a Latex file as a text document is not WYSIWYG, while authoring a word document is. Writing a HTML document with a text editor is not WYSIWYG, while writing it with an authoring tool is. +------------------------------------------------------------ | WORM +------------------------------------------------------------ WORM a program that connects to other machines and replicates itself. Worms have the potential to both damage infected machines and to interfere with networks and services due to congestion caused by the spread of the worm. +------------------------------------------------------------ | WORM +------------------------------------------------------------ XHTML 2 is a general purpose markup language designed for representing documents for a wide range of purposes across the World Wide Web. To this end it does not attempt to be all things to all people, supplying every possible markup idiom, but to supply a generally useful set of elements. Here is an element of a XHTML 2.0 document: Virtual Library

Moved to vlib.org.

+------------------------------------------------------------ | XML +------------------------------------------------------------ XML The Extensible textbased Markup Language is a format for structured documents and data on the Web. It is derived from SGML (ISO 8879). XML is also playing an increasingly important role in the exchange of a wide variety of data on the Web. +------------------------------------------------------------ | XviD +------------------------------------------------------------ XviD XviD is a word play, read it the reverse way and you might find a familiar term. XviD is an open source MPEG-4 codec which depending on whom you're asking yields even better quality than the best DivX codec. +------------------------------------------------------------ | zombie +------------------------------------------------------------ zombie A unix process that has died but has not yet relinquished its process table slot. The parent process hasn't executed a "wait" for it yet). This file is part of the Sofia project sponsored by the Provost's fund for teaching and learning at Harvard university. There are 108 entries in this file. COUNT: 108