A client-server application is an application that runs on a client device and communicates with a server device over a network. The client device requests data or services from the server device, and the server device responds to the requests. A spreadsheet software that connects to a remote database is an example of a client-server application. The spreadsheet software acts as the client, and the database acts as the server. Reference : The Official CompTIA IT Fundamentals (ITF+) Study Guide (FC0-U61), page 128.