Business Definition: A software testing technique performed post software build to verify that the critical functionalities of software are working fine. It is executed before any detailed functional or regression tests are executed. The main purpose of smoke testing is to reject a software application with defects so that QA team does not waste time testing broken software application. Technical Definition: Also known as confidence testing, sanity testing, build verification test and build acceptance testing, smoke testing is preliminary testing to reveal simple failures severe enough to, for example, reject a prospective software release. Smoke tests are a subset of test cases that cover the most important functionality of a component or system, used to aid assessment of whether main functions of the software appear to work correctly. It is a set of tests run on each new build of a product to verify that the build is testable before the build is released into the hands of the test team.