Client-Server Architecture: It is network architecture in which each and every computer or process on the network is either a client or a server. The Servers are powerful computers or processes devoted to managing disk drives (that is, file servers), printers (that is, print servers), or network traffic (network servers). Clients are PCs or work-stations on which users run applications. The Clients rely on servers for resources, like devices, files, and even processing power.
The other kind of network architecture is termed as a peer-to-peer architecture since each node has equivalent responsibilities. Both client-server and peer-to-peer architectures are broadly used, and each has exclusive merits and demerits.
Client-server architectures are at times termed as two-tier architectures.