In information technology, gap analysis is an assessment tool to help identify differences between information systems or applications. A gap is sometimes called "the space between where we are and where we want to be."
A gap analysis helps bridge that space by highlighting which requirements are being met and which are not. The tool provides a foundation for measuring the investment of time, money and human resources that's required to achieve a particular outcome.
In software development, for instance, a gap analysis can be used to document which services and/or functions have been accidentally left out, which ones have been deliberately eliminated and which still need to be developed. In compliance, a gap analysis can be used to compare what is required by law to what is currently being done.