Every home or office computer need an input device, this is just a device that allows the user to interact with the computer. There are many different types of input device but the most common is the keyboard and mouse or if you have a laptop then a keyboard with a built in touchpad.
When you buy a new computer you will usually get a wired keyboard and mouse. Whilst these are functional and will do the job they are not as flexible as a wireless alternative. Wireless means that there are no wires and instead of connecting the device to the computer with a lead you instead connect using a wireless connection. This means a small device that plugs into your computer and sends out the wireless signal. The wireless keyboard will then be able to connect to your computer via the device that you have connected to your computer.
You can buy a separate wireless keyboard and a separate wireless mouse if this is the type of input device that you are used to. Many people prefer using a mouse rather than a touchpad, trackpad or trackball. You cannot however get a keyboard with a built in mouse, instead you can get a keyboard with a built in touchpad, just like on a laptop keyboard or with a built in trackball.
A wireless keyboard touchpad combination is good if you prefer using or are used to using a laptop keyboard. It is also preferable if you have a home entertainment computer or a HTPC. A media PC is basically a computer that plugs into your television and is used to play video and music mainly but also can be used to send emails or browse the internet. These types of computer are designed to specifically to be smaller, quieter and blend in with most home entertainment systems.
Using a wireless keyboard with touchpad means that you can sit on your sofa and control your computer without any leads. The keyboard connects through the wireless device that is plugged into the back of your PC, these come with the wireless keyboard. The wireless keyboard and touchpad unit is usually powered by batteries, these are either standard batteries that you can buy from any shop or the unit may come with a built in lithium battery which is generally the case for more expensive models.