(1) In communications, a line, channel or circuit over which data are transmitted.

(2) An address that points to a Web page or other file (image, video, PDF, etc.) on a Web server. Links reside on Web pages, in e-mail messages and word processing documents as well as any other document type that supports hypertext and URL addressing. See URL and hypertext.

(3) In data management, a pointer embedded within a record that refers to data or the location of data in another record.

(4) In programming, a call to another program or subroutine.