To make available. When software "exposes" certain functions, it makes those routines available to the programmer through a programming interface (API). If a company "exposes" its Web services, it is making certain services available to users or to other companies over the Web.
(Exposé) A feature of the Mac OS X operating system, starting with Version 10.3, that shrinks all open windows and displays them side-by-side. It is similar in purpose to the Flip 3D feature in the Windows Aero interface. See Flip 3D
All Windows Displayed
Expose displays all open windows so that users can quickly decide which one they want to jump to.