Given that a decision has been made to install a network. What kind of network should be used? There are two main network topologies available, namely Client-Server and Peer-to-Peer (don't get these mixed up with layouts i.e. star, ring and bus)
This mini-web will describe both types and then compare and contrast them so that you understand the logic of using one over the other.
A basic introduction to peer-to-peer and client-server networks can be read here