UCS: The Ultimate Computer Source
A Thinkquest 1999 Entry

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Packet Switching

Packet switching refers to how data packets (data traveling to or from a server) are divided into chunks, each chunk possessing the desired data, the server it came from, and the server its going to. After it gets to the intended source, the packets are put back in order.

Pascal

A somewhat educational programming language designed to teach advanced programming methods and to be a stepping stone to C.

Perl

Perl is a language usually used to make programs for CGI, like guestbooks, administration tools, counters, and others.

Petabyte

An exabyte is 1000 petabytes. A petabyte is 1000 terabytes. A terabyte is 1000 gigabytes. A gigabyte is 1000 megabytes. A megabyte is 1000 kilobytes. A kilobyte is 1000 bytes. A byte is 8 bits. A bit is either a 0 or a 1, which is true or false, on or off symbolically.

Anything that is 1000 of something is not 1000 of it literally. For example, a megabyte is not really 1000 kilobyte, but is close. Most memory names (exa peta tera giga mega kilo) are 1024 of the name lower than them, but it's usually rounded off to 1000.

Ping

A ping is a small network signal sent to a server intended to be bounced back to the original computer. It is used to measure latency (slowness) between the two computers. A ping is similar to a hop time on a traceroute.

Plug-in

A plug-in is a (usually) small program or data that can be added to a larger program, adding new features to that program. Without plug-in's, a person could have to download a program each time just to get the new features, and for a program like Netscape, that would be way too time consuming. Programs like Netscape and Adobe Photoshop use plug-ins. Plug-in's could also be called addons.

POP

Pop can mean one of things:

1. Point of presence. A point of presence is an area (like a city or a town) where a network is connected to. A point of presence could be used to make dial-up internet access, for instance

2. Post Office Protocol. Post Office Protocol is the way in which email programs like Netscape mail, Eudora, Pegasus, and others receive mail from a mail server. Sending mail involves an SMTP server, using its own protocol.

Port

Port can mean one of a few things:

1. A physical port allowing for a wire connection or a plug, like a serial port.

2. Every network node has ports, which are just numbers from around 1 to 99999. Ports are just used to access different programs that may be running on the same address. Every server daemon operates on a port, like a MUD, a UNIX login (default port 23), a web server (default port 80), or an IRC server (default port 6667). Some daemons automatically connect you to the right port, that's why you may not notice it all the time. Just telnetting to a server probably leads you to port 23. Accessing an HTTP server usually automatically sends you to port 80.

3. A version of a program that is made to run on another operating system, like a port of Pine (a UNIX email program) to Windows.

PPP

PPP stands for Point to Point Protocol. It is the protocol that allows a computer to access TCP/IP and actually be on the Internet.

Print Spooler

A print spooler intercepts print information, and then spools it into the printer when it is convenient. It is essentially background printing. This allows for much speedier printing. The actual term spool is an acronym that stands for Simultaneous Peripheral Operation On Line.

Programming

Programming is the coding of programs in instructional form. While to a novice computer user some programs seem magical and easy to use, in general, programming powerful programs is difficult and time consuming. Some languages have been made as stepping stones to others. Here is a semi list of popular languages that when learned in order can make learning programming easier:    Logo
   Basic
   Pascal
   C

Protocol

A protocol is a set of instructions and rules that are followed when information is exchanged. A protocol handles exchanged information.

Proxy

A proxy is a server that acts as a firewall between a user an a network in that the user is connecting through the proxy server, which sort of relays the network signal to the target desired. The benefit of this (for an ISP running a proxy for web access) is controlled security and added user protection.


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QWERTY

QWERTY is a kind of layout for a keyboard. It is derived from the first letters on the keyboard on the top in order, Q W E R T Y. QWERTY keyboards are the standard and default keyboards used today. Another, less kind of used keyboard is a Dvorak keyboard, made by a man who believed that keys should be arranged based on how often they're used. So the E key would be on the "home row," and the Z key would not be in such a convenient location.


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rlogin

Rlogin stands for Remote Login, and allows someone to work on one computer, but execute commands on another, remotely.

Router

A router is a computer or software that handles incoming and outgoing network packets. A router spends all its time scanning a packet, and routing it to wherever it needs to go.


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Server

A server usually means a computer connected to the internet running some type of server daemon.

Shell

A UNIX or Linux (or clone)'s command interpreter. A shell is a program which reads, interprets, and executes commands that you input. Some popular shells are Bash, Tcsh, and Csh.

SLIP

SLIP stands for Serial Line Internet Protocol. It allows for a computer to become a real site on the Internet, similar to PPP. SLIP is becoming less and less used as people switch over to PPP.

SMTP

SMTP stands for Simple Mail Transfer Protocol. It is the protocol used by email programs to send mail to other email accounts.

Spam

Spam can mean a few things:

1. Unsolicited mail that either contains an advertisement, pornography, or something equally useless and or annoying.

2. On a talker or mud or system in which a user fills the screen with text in order to annoy everyone.

Spamming is (as of time of print) only illegal in California, but is highly immoral and goes against everything the Internet has become to be and stands for.

Spanning

Spanning is a process/technique in which a large file is split up into smaller files so that the file can be divided over multiple floppy disks. For example, by spanning a five megabyte file, a user could place the file on 3-4 floppies since a standard floppy disk can only hold about 1.4 megabytes.

Spider (Web Spider)

A web spider is a robot used by search engines to map out web sites, by accessing every link on a site, then every link on each links site, etc. This can lead to a very powerful search engine database, such as Altavista.

SQL

SQL stands for Structured Language Query. It is a programming language used to interact with information in a database. While each SQL program has its own unique features, all programs made with it support a common amount of it in them automatically.

SSL

SSL stands for Secure Sockets Layer. It is a protocol made by Netscape to enable secure encryption of data over the Internet.

SVGA

SVGA stands for Super Video Graphics Adapter. It supports many resolutions and up to 16 million colors.

Symbolic Link

A symbolic link is an alias of a file or a directory. For example if a directory was pub/files/programs/windows/browsers/netscape/netscape4, that would be very inconvenient. A symbolic link could refer to it as 'netscapev4' and if someone entered that directory, it would in fact take them to pub/files/mystuff/programs.... and so on.

SysOp

Sysop stands for System Operator. A SysOp is usually the maintainer/boss of a networked system, like a BBS, a Talker, a MUD, IRC, etc.


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T-1

T-1 is a high speed connection used in most network servers. It is capable of speeds of 1,544,000 bits per second, which is a megabyte in less than 10 seconds.

T-3

T-3 is an even higher speed connection on a dedicated line used by only advanced networks due to their cost. It is capable of speeds of 44,736,000 bits per second, which is more than enough for full motion full screen video over the Internet, which is 10,000,000 bits per second.

Talker

A talker is similar to a MUD only it involves more social interaction than a MUD. One of the most popular Talker systems is Nuts (by Neil Robertson), all though there are many other systems like IForms, and many many Nuts rewrites.

TCP/IP

TCP/IP stands for Transmission Control Protocol/Internet Protocol). It is the most used network protocol ever created. It is used to enable computers to communicate with each other. HTTP, rlogin, telnet, FTP, and other such things all utilize TCP/IP.

Telnet

Telnet is a protocol that allows client programs to connect to 'ports' or 'sockets' of host servers. Telnet uses text, and has become the home of countless MUDs, Moos, and Talkers. But Telnet can also be used to access mail servers, UNIX logins, and other server daemons that run with text on a server port.

Terabyte

Approximately 1000 gigabytes of information. Terabytes are only used by big corporate companies as of yet, due to their high cost.

Terminal

A terminal is a computer that is used to send commands to another system. Some telnet programs emulate terminals when accessing systems like a UNIX system.


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URL

URL stands for Uniform Resource Locator. It is used to refer to certain computer or certain files on a computer. This is usually used for web pages. Basically, a URL is a web site address. HTTP//www.advanced.org is a URL.

Usenet

Usenet, or news is a bulletin board system made up of servers that contain messages left by users, who can post their ideas or thoughts, or respond to someone else's message. It has been estimated to reach about 10 million people overall.

UUENCODE

UUENCODE is a protocol similar to BinHex in that it converts unattached binary packages into text to be transmitted through email.


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Variable

A variable is used in program to assign information to a keyword to be used later in the program.

VGA

VGA stands for Video Graphics Adapter. It was developed by IBM in 1987 to replace the inadequate EGA made by IBM a few years before. VGA is a video mode that supports up to 250 colors, a bare minimum for sold computers today in the field of graphics.

Virus

A virus is a program that sneaks its way onto computers to either disrupt files on a computer, launch prank type messages or sounds, or reproduce itself so many times that the hard drive is filled to the maximum and the computer is disabled. Viruses are forms of warfare that have become the fear of many system administrators and computer owners, causing them to use Virus Detecting/Cleaning programs to remove them.

VRML

VRML stands for Virtual Reality Modeling Language. It is a programming language that allows creation of 3d environments by use of Polygon creation, and the ability to change light positions.


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WAN

WAN stands for Wide Area Network. It is like a LAN in that connected computers to the WAN share resources and data, but a WAN can have computers connected from distances larger than computers connected to each other in a college campus.

Wais

Wais is an internet information database service that makes finding information easier when using a web sites internal search engine.

Warez

Warez is a term meaning illegal pirated software.

Webmaster

The owner or maintainer of a site or webpage is usually called the Webmaster of the page.

Wildcard

A wildcard is something like ? or * which is used to stand for 'anything.' For example, in UNIX, if you wanted to delete all 50 text files in a directory, file1.txt, file2.txt, etc, it would take way too long to type rm file#.txt one at a time. A wild card could be used, such as: rm *.txt. That means "Remove anything.txt, which is every text file in the directory."

WWW

WWW is the World Wide Web. It is a collection of servers, databases, and programs that are connected to each other by means of HTTP, FTP, Gopher, etc. It allows people to retrieve such vast amounts of data that it has been one of the most important technological developments of our time in the area of communication and sharing of knowledge.