How To setup a LAN

What is a Network?
A Network is simply the infrastructure that connects a number of electronic devices so that data can be transferred between them. By devices I could mean computers (PC's, Apple Mac's, PDA's) or printers, scanners, modems, CD room, etc.
In this page I will refer mainly to computers instead of devices. Oh and by the way, I'm primarily a PC man so when I say computer I'm usually thinking of a PC. Please ask in the forum if you have another system and are not sure about something.
What types of Networks are there?
Networks can take many different physical forms. The main categories of networks in order of distance are: (PAN) Personal Area Network Used to connect wireless devices carried by a person (e.g. PDA, mobile, etc.). The Bluetooth technology is currently the prime contender for this LAN Local Area Network Used to connect computers in a building wLAN Wireless Local Area Network Used to connect computers within a 100m (300ft) range without wires MAN Metropolitan Area Network Used to connect computers in a town/city WAN Wide Area Network Used to connect computers whatever their location
If you are more interested in this, try looking up network topologies and technical terms in webopidia and what is and current.
Do you need a LAN?
First of all - do you need a LAN? Well that depends on what you want to do...
A LAN will allow you to:
Allow all of your computer to share an Internet connection
Share data (e.g. Word documents, music, video and any other type of file) between computers
Share printers, scanners and other networkable devices
Stream music and video from one computer to another (as opposed to downloading and then running locally)
Play multi-player games
Backup data
Video-conference (e.g. from one room to another)
etc.

Cabling

Although you can buy cables at specific lengths (e.g. 2 metres, 5 metres, 10 metres, etc) , or even buy them to your specified measurements, it is often easier to make them yourself. This way you can make them to the required length.
Here I have explained how to make cables for
What you will need:
Length of the UTP (Unshielded Twisted Pair) cable (e.g. xx metres) UTP RJ45
RJ45 Plugs
RJ45 cable boots (1 for each RJ45 plug) not essential but preffered as they re-enforce the fitting of the cable into the RJ45 plug
RJ45 Crimp Tool
The RJ45 plugs should have the following wire order: (where pin 1 is on the left when you look at the RJ45 plug from behind and it is upside down - i.e. the latch that sticks out is pointing down and towards you)

To make the cables :
Cut the cable to length
Strip the ends cable (the crimp tool will probably have a wire stripping gizmo on it to strip the wires to the right length)
Put the RJ45 cable boots onto the cable (you do not actually need these, but they do serve three purposes:- They look good, they help prevent damage to the cable from bending just behind the RJ45 plug and if you use different coloured boots, they can help identify which cable in the hub the individual wires into the RJ45 plugs (in the order shown in the tables above)
Use the crimp tool to crimp the wires into the plug. double check that the wires are in the correct order, have been crimped properly, etc.