Client software refers to applications that run on a user's device, allowing them to interact with a server or a service over a network. Examples include web browsers, email clients, and messaging apps. These programs send requests to servers, which process the information and return the results to the client for display or further action. Typically, client software is designed to provide a user-friendly interface, making it easier for individuals to access and manage data. It relies on protocols like HTTP for web browsing or SMTP for sending emails, ensuring smooth communication between the client and the server.