Router: The most important piece of hardware on a home network. A router does exactly what it says it does; it routes data to the computers on a network. It basically connects all your computers and your broadband/cable modem together, allowing all the computers to browse the Internet at the same time. A router adds a level of security between your computers and the Internet and so should be your most important line of defence against malicious attacks. Most routers, such as the Netgear routers have built-in software that provides anonymity on the Internet, protecting your family. Using a broadband cable or DSL modem without a router will leave you open to hackers and other online threats.

Hub: A device used to connect PCs to a network via Ethernet cabling or via Wi-Fi. Wired hubs can have numerous ports and can transmit data at speeds ranging from 10 Mbps to multi-gigabyte speeds per second. A hub transmits the packets of data it receives to all the connected ports. A small wired hub may only connect four computers; a large hub can connect 48 or more. Wireless hubs can connect hundreds.

Switch: A type of hub that efficiently controls the way multiple devices use the same network so that each can operate at optimal performance. A switch acts as a networks traffic police: rather than transmitting all the packets of data it receives to all ports as a hub does, a switch transmits packets to only the receiving port. Switches are fast replacing hubs as a preferred choice of data management as prices are more in line with hub prices.

NIC (Network Interface Card): A type of PC adapter card that either works without wires (Wi-Fi) or attaches to a network cable to provide two-way communication between the computer and network devices such as a hub or switch. A Network interface card can be installed internally into a desktop PC or slotted into a Type 2 PCMCIA slot on a laptop or PDA.

Combined switch/router: A popular choice of Access Point as it combines both the functionality of a router and switch in one unit.

• USB Adapter--choose this adapter for a desktop with an available USB port
• PC Card/Notebook Adapter--about the size of a credit card, this type of adapter is used on a laptop and installed in the PCMCIA slot
• PCI Adapter--choose this adapter if you are comfortable opening your desktop or you don't have an available USB port.

• Hub--this hardware is what all your computers connect in to. All data received is sent to all connected ports on the hub. This can be easily substituted for a router or switch that distributes data more efficiently
• Network adapter/network interface cards--one for each of the PCs or laptops you want to connect to the network
• Network cables--one cable from each of the computers to the hub is required. Standard modem and printer cables can be used to connect these devices to a PC

Setting up a network with this configuration will require Internet and printer sharing to be enabled. This is done via your computer's operating system. It is worth noting however, that Internet sharing via a USB-connected broadband modem will be slower than connection via an Ethernet ADSL/broadband modem through a router.

• Wireless router--this Internet-sharing device connects all your computers to the Internet and to one another. It connects to your cable modem or set-top box via an Ethernet/network cable.
• Network cables--one connects your wireless router to your cable modem or set-top box, the other connects the router to one computer.
• Wireless network adapters--one of these is required for each computer on the network. There are three different types of adapter to choose from: USB wireless network adapter, internal PCI wireless network card for desktop PCs and PC/PCMCIA wireless network adapter cards for laptops.

Do be aware that to set up an Internet-sharing network with this configuration, your broadband/cable modem must have an Ethernet connector to enable it to connect to the router. If you have a standard USB ADSL modem without an Ethernet connection, Internet sharing is still possible, it is just configured differently. The broadband modem is connected via USB to one of the computers on the network. However, Internet sharing via a USB-connected broadband modem will be slower than connection via an Ethernet ADSL/broadband modem through a router.

Access Point: the base-station that connects wireless devices to your wired network (or in some cases to another access point). Depending on the set-up of your network, the connection might link to a single computer, a hub that links many computers together or directly to an ADSL or cable modem. There are a number of different types of access point used in both wireless and wired networks but their basic function is always the same: to ensure sure data makes its way correctly from one point to another. Confusion can sometimes be caused because the differences between the different types of access point are not always precise. Hubs, bridges, switches, routers and gateways can often share certain capabilities or be found combined together into a single box.

Ad-Hoc Networking: the term used when computers equipped with wireless networking facilities create a mini-network by connecting directly to each other rather that through an access point or wireless hub.

Bandwidth: usually measured in Kbps or Mbps (kilobits per second or megabits per second respectively, where 1 Mbps = 1024 Kbps), bandwidth refers to the amount of data that can be transmitted across a network at any point in time.

A much used comparison when talking about bandwidth is that of a water pipe. A small pipe can only carry a trickle of water whereas a bigger pipe can carry a torrent. It's the same for information and bandwidth--the higher your bandwidth, the more information can flow at any point in time, leading to faster downloads and file-transfers.

To give an idea of what these numbers mean it may help to know that a standard modem connection to the Internet crawls along at 56 Kbps while broadband connections speed along at anything from a more healthy 512 Kbps to a rocketing 2 Mbps.

Home networking speeds vary depending on how you connect your devices. Basic Ethernet (cabled) networks, known as 10BaseT, offer a bandwidth of around 10 Mbps although Fast Ethernet (100 Mbps) and Gigabit Ethernet (1000 Mbps) are becoming popular but require newer or more expensive technology. Wireless networks largely fit into three categories known as 802.11b (11 Mbps max.), 802.11g (54 Mbps max.) and 802.11a (also 54 Mbps).

Bridge: a bridge is a networking device used to connect one network to another. Wireless bridges, for example, are a good way to link a network on one floor of a building to a network on a different floor, where traditional wiring might be problematic or impossible.

Crossover Cable: a crossover cable is a specially wired cable that allows the direct connection of one computer to another without the use of a hub or other networking device. A crossover cable may also be required when connecting a cable or ADSL modem directly to a wireless gateway or access point. If in doubt refer to your equipment's operating instructions.

DNS (Domain Name System): a system that works behind the scenes to make Web surfing easier by translating standard URLs (eg: www.halfvalue.co.uk) to the numerical equivalent that computer systems use internally to uniquely identify every website on the Internet. This numerical equivalent is called an IP address, and is represented by a series of numbers separated by full-stops (eg: 197.30.62.7).

Ethernet: an international standard for networking computers together using cables. Invented in 1973, this standard has been around for quite some time but has expanded to offer faster networking speeds as computer technology has progressed. Basic Ethernet networks, known as 10BaseT, offer a bandwidth of around 10 Mbps although Fast Ethernet (100 Mbps) and Gigabit Ethernet (1000 Mbps) are becoming popular but require newer or more expensive equipment and cabling.

Fast Ethernet: (see Ethernet)

Firewall: a piece of software or hardware that protects a computer system by preventing unauthorised access. Firewalls work by policing and controlling the information that is allowed both into and out of the network.

Gateway: a gateway is an access point (wired or wireless) that provides additional capabilities often including NAT, DHCP or firewall functionality.

Gigabit Ethernet: (see Ethernet)

Hub: a hub is the computing equivalent of the standard four-way extension sockets everyone is familiar with. In networking terms this refers to a device that lets you connect a number of computers to a single point. In practical terms this means that hubs tend to be small boxes with a number of Ethernet sockets (generally four or eight, although some large hubs may have as many as 48). Wireless hubs are also available for sharing information in a wireless network.

Unlike a switch, a hub is an unintelligent device and does not make any judgements about what data should be directed to which of the connections. Instead, each piece of data (known as a packet) sent to the hub is redirected to every connection and disregarded by all except for the device for which it is intended.

As with any networking device the speed at which data moves through the hub is determined by the amount of bandwidth the hub is designed to handle This means it is wise to check a hub's specifications before purchasing if speed is likely to be an important issue.

IP (Internet Protocol) Address: a numerical code used to uniquely identify every computer on the Internet. This 32-bit (bit = binary digit, i.e., 0 or 1) code is usually written in the form of four decimal numbers, each under 256, separated by full-stops--for example 197.30.62.7. Part of the number represents the location of the computer's home network on the Internet while the remaining portion identifies where the computer's individual location on the network.

In a home network, this protocol (a standard for exchanging information) is used to help the computers to exchange information with each other as well as with other computers on the internet. No two computers can use the same address or the network will not work correctly.

LAN (Local Area Network): a network that connects computers together in a small, easily defined area, such as a room, building or campus.

NAT (Network Address Translation): NAT is a facility often found in routers, access points or software that enables you to share a single incoming internet connection (using a single IP address) with a number of computers. It works by creating new IP addresses for each machine on your network and intelligently routing incoming and outgoing network traffic to the appropriate computer.

Network Card: also known as a NIC (Network Interface Card) this is an adaptor that gives your computer the ability to connect to other computers and network devices, either wirelessly or using cables.

Network Name: identifies your network. Different network names are required when setting up your individual computer, wired network, wireless network or workgroup. In wireless networking the network name is often referred to as the SSID.

PCMCIA Card: a removable device, not much bigger than a credit card and varying between 3.3 mm and 10.5 mm in thickness, used to extend the capabilities of PCs, laptops and PDAs. Typically PCMCIA cards are used in networking as modems, or to add Ethernet or wireless networking facilities to computing devices.

Proxy Server: a method used to improve network operations or security. A proxy server is a computer that acts as an intermediary between two networks or between a network and the internet. Proxy servers are commonly used by Internet providers to improve the speed of Internet connections by caching (storing) frequently requested internet pages so they can be delivered to local users without having to fetch them from distant Web servers.

Router: a device that forwards data from one network to another or moves data around within a network. Based on rules, routers calculate how to send information from one place to another via the most efficient route avoiding any problems it encounters during the process.

Server: a computer that provides resources or data to other computers or devices on a network. Common examples include Web servers, print servers and data servers.

SSID (Service Set Identifier): (see Network Name)

Switch: much like a hub, a switch is a device with many network ports, designed to allow a number of devices to simultaneously function from a single network point. Unlike a hub however, a switch intelligently transmits information only to the port for which it is intended, greatly improving the efficiency with which the network's bandwidth is utilised.

Wi-Fi (Wireless Fidelity): Wi-Fi is the somewhat catchier name for the set of wireless networking standards also known as IEEE 802.11b, IEEE 801.11a and IEEE 802.11g.

Products certified to conform to the Wi-Fi standards are interoperable with each other even if they are made by different manufacturers. IEEE 802.11b is the slowest of the three standards, running at 11 Mbps compared to the 54 Mbps that is offered by each of the others. However, when different versions of the standard are used together they continue to communicate, albeit at speed determined by the device with the lowest available bandwidth.

Access points that use Wi-Fi networking are beginning to pop up in hotels, shopping centres and other public places around the world, giving owners of Wi-Fi enabled devices the opportunity to connect to the Internet at these locations, either for free or after paying a small fee.