You carry out this testing at the initial stage of software development to check whether your application performs basic functionalities or not.
By Testgrid
It should be scripted and documented. This testing can be stable as well as unstable. It should be carried out by the quality assurance engineers only.
Detect any early defects in software products. Demonstrate system stability. Assure that even the minute functionalities of the program are working fine.
It will check if the basic features are working correctly or not. When there is a change in the build, or a new build is delivered, this testing technique should be used.