A build is an operational version of a system or part of a system that demonstrates a subset of the capabilities provided in the final product.

Builds are an integral part of the iterative lifecycle. They represent on-going attempts to demonstrate the functionality developed to date. Each build is placed under configuration control in case there is a need to roll back to an earlier version when added functionality causes breakages or otherwise compromises build integrity.

During iterative software development there will be numerous builds. Each build serves to provide early review points and helps to uncover integration problems as soon as they are introduced.