An application that runs on a personal computer or workstation and enables you to send, receive and organize e-mail. It's called a client because e-mail systems are based on a client-server architecture. Mail is sent from many clients to a central server, which re-routes the mail to its intended destination.
A program that can retrieve email from an email account, allowing a user to read, forward, delete, and reply to email messages. Popular e-mail clients include Outlook Express, MS Outlook, Eudora, and Incredimail.