Application

On all macs, classic through OS X, standalone programs have been known as Applications (or Apps).

In layman's terms, apps are the pieces of software that build up an operating system. For instance, a Mac™ would be virtually useless without any web browsers, text/image/audio/video editors/viewers, games, instant messengers, directories, mail readers, etc., especially without the finder which lets you control your handle, preview, and in the cases of picture clippings and text clippings, read files.