By themselves, computers are powerful tools. When they are connected in a network, they become even more powerful because the functions and tools that each computer provides can be shared with other computers. Networks exist for one major reason: to share information and resources. Networks can be very simple, such as a small group of computers that share information, or they can be very complex, spanning large geographical areas. Regardless of the type of network, a certain amount of maintenance is always required. Because each network is different and probably utilizes many diverse technologies, it is important to understand the fundamentals of networking and how networking components interact.