Data sent over a network is sent in packets. Each packet has a header and a payload. The header helps identify the packet as part of a message, and the payload carries actual information (such as a piece of an e-mail, a part of an image, and so on).
Mbps (megabits per second): Refers to how the speed on a network is measured and is used to describe the bandwidth. A 10 Mbps network connection allows you to send data at the theoretical rate of 10 megabits per second.

This is theoretical because a network connection is just like a highway or road. One might say that a certain road can carry up to 500 vehicles per minute, but placing that many cars on the road would make for a very congested road. The more congested the road, the less useful it is, and the slower the traffic goes. It is the same with a network. If you share a 10 Mbps wireless connection that's fully utilised, what you'll end up with is a very slow connection -- it's literally bogged down with data packets.

To ensure that a computer has the fastest connection, locate it as close to the access point as possible.