Avatar - A small ico that represents a real person in cyberspace.
Cache -  computer memory that holds most recently used data
Cookie - A tiny piece of text placed on a hard drive that allows a web server to store information about the user on his computer. Cookies record bits of information such as shopping purchases and user name and password.
Compression -  reducing the size of a file. Some common compression standards are Zip files for the PC, Stuffit files for the Mac, and MP3 files for music compression.
Default Settings - The settings that the computer uses at the startup of a program or operating system.
Driver - Software that the computer needs to understand how to operate a monitor, printer or other attached device.
Ethernet Card - A piece of computer hardware that enables communication between computers on a network
Firewall - A type of Internet security (software or hardware) that protects a computer or a computer network from unauthorized access.
JPEG (Joint Photographic Experts Group) - The most commonly used format for image files, often preferred for photographs.
Motherboard - The main circuit board of the computer.
Operating System (or OS)- A computer program that acts as the link between the computer and the user  

script kiddies pl.n.

1. [very common] The lowest form of cracker; script kiddies do mischief with scripts and programs written by others, often without understanding the exploit they are using. Used of people with limited technical expertise using easy-to-operate, pre-configured, and/or automated tools to conduct disruptive activities against networked systems. Since most of these tools are fairly well-known by the security community, the adverse impact of such actions is usually minimal.