Terminology

Firewall - Used to keep your internal network secure. Protects one or more computers in your network from hackers on the Internet. Software and hardware firewalls are available.

Software Firewall - An application that is running on each computer needing to be protected. These products are designed to detect and stop many types of attacks on your computers. Software firewalls can also manage and restrict applications running on your computer from accessing the Internet. The disadvantage to a software firewall is that it can decrease overall system performance, as it is an additional application running on your computer all the time.

Hardware Firewall - A self-contained box that is inserted between your DSL or Cable modem and your internal network. It blocks attacks from hackers on the Internet before they reach any of your computers. It also provides the capability of protecting more than one computer on your high-speed Internet connection.
 
Higher end equipment includes additional capabilities such as activity logging, VPN access, content filtering, and antivirus scanning as well as many other functions. The hardware firewall is an independent system and will not slow down your computer system. A possible disadvantage is the inability to monitor and/or restrict out bound Internet access by individual applications.

DSL - Digital Subscriber Line - A recently developed (late 1990s) digital communications technology that can provide high-speed transmissions over standard copper telephone wiring.

Cable modem - A device which provides high-speed Internet access via a cable TV system. The modem converts a digital signal on the coaxial cable in your home to a format that can be used by your computer.

Antivirus Software - Designed to detect, identify, and eliminate viruses attached to files and e-mail coming to your computer. Whether connected to the Internet or not, it is always recommended to have antivirus protection on all computers as new viruses are discovered daily.
 
The two primary antivirus software products are McAfee and Norton/Symantec. Both products require updates - which can be configured to be automatically downloaded and installed from the Internet on a daily basis.

Wired and Wireless Networking - Wired networking usually consists of physical networking equipment and software drivers. The most common wired network is "Ethernet". Wireless LANs are often used in settings where a user must carry a portable computer from place to place. These wireless networks use radio, microwave, or infrared to transmit information.

NIC - Network Interface Card - An add-in card that is plugged into the computer. It allows the computer access to other equipment on your network, such as other desktop computers, servers, printers, and other network devices.

Device Drivers - Software that teaches an operating system, such as Windows XP, how to communicate with any device attached to your computer. Devices include monitors, sound cards, scanners, printers, and any other peripherals that connects to your computer.

Hub - A piece of equipment that is used to connect two or more computers together. This inexpensive solution is designed to repeat the data from one computer to all computers connected via the hub. Hubs can be connected together to increase the number of connected computers.

Switch - Functions like a hub but more efficient and can improve traffic across the network.

Cat5 Wiring - Category 5 cable - Cabling quality has been categorized starting with Cat1 as the slowest to the current Cat6, which is the fastest. Cat3 is generally used for phone lines. Cat 5 is generally used for computer networking, while Cat 5e and 6 are used for high-speed networking.

Router - This piece of equipment, or software, "routes" network traffic between two or more networks. Some routers are very simple and move all traffic between networks going in both directions. More expensive routers have programmable options that control what traffic gets to be routed to which networks in addition to blocking traffic in one direction but not in the other.

References

1.  Microsoft Computer Dictionary, Fourth Edition; Microsoft Corporation, Copyright 1999.
2.  TechWeb: The Business Technology Network: www.techweb.com/encyclopedia