V model is a process model that helps in improving the quality of the software product by combining Software Development Life Cycle & Software Testing Life Cycle. In this model both work parallel. The left hand side of the V model contains SDLC in down-hill direction & the right hand side of the V Model contains STLC in up-hill direction. For every development phase there is a testing phase. Development phases are called as verifications & testing phases are called as validations