The Online World resources handbook

Frequently used terms http://home.eunet.no/~presno/bok/v4.html
TAR
.TAR or .tar is a file name extension used by a Unix utility for archiving files, often used
with "compress." The resulting files can contain both files and directories, and may
include the subdirectory structure needed to restore the files. The way in which a
"tarred" file is "untarred" depends on the operating system you are using. Utilities to
extract on DOS machines may be retrieved from many sources around the net.
Terminal emulator
A program that allows a computer to emulate a terminal. The workstation appears as a
given type of terminal to the remote host.
Unicode
A 16 bit standard system for encoding characters of all the world's languages. The first
128 codes of Unicode are the same as in ASCII. The system uses two bytes for each
character rather than one, and can handle 65,536 character combinations rather than
ASCII's just 256.
Unicode can house the alphabets of the world's languages, including a complete
complement of Chinese, Korean and Japanese specific characters. ISO defines a
four byte character set for world alphabets, but uses Unicode as a subset.
Unix
An operating system that supports multi user and multitasking operations.
Uploading
The act of transferring data from your computer's disk (up) to an online service and
storage there.
Virus
A computer virus is a small computer program created by a computer literate vandal
with the purpose of destroying data or even applications programs in other people's
computers.
VRML
The Virtual Reality Markup Language aims at extending the World Wide Web into the
domain of three dimensional graphics. VRML "worlds" can depict realistic or
otherworldly places, which can contain objects that link to other documents or VRML
worlds on the Web. For information, see The Virtual Reality Entertainment Resource
Guide.
X.25
A ITU TSS standard communications protocol used internationally in packet data
networks. It provides error checked communication between packet data networks and
their users or other networks.
Rather than sending a stream of bits like a modem, an X.25 router sends packets of
data. There are different packet sizes and types. Each packet contains data to be sent,
information about the packet's origin, destination, size, and its place in the order of the
packets sent. There are clear packets that perform the equivalent of hanging up the
phone. There are reset, restart, and diagnostic packets. On the receiving end, the packet
assembler/ disassembler (PAD) in the router translates the packets back into a readable
format.
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