Definition of lock

A software security feature that requires a key or dongle in order for the application to run correctly.

To block other meeting participants from controlling the Office Live Meeting 2007 client during a presentation.

To prevent users from joining a conference, whether or not they have an invitation.

A restriction on access to a resource in a multiuser environment.

To protect an object from being modified.

Ensure that two processes do not affect the same file or project in a database at the same time.

A data structure used to synchronize access to a shared resource. The most common use for a lock is in multithreaded programs where multiple threads need access to global data.