After completion of test cases selection & their review, testing team concentrates on build release from development and test execution on the build.
Level 0: ( Sanity/smoke testing)
After receiving initial build test engineers concentrate on Basic functionality of that build, to estimate satiability for complete testing. In this sanity testing test engineers try to execute all end to end & integration test cases OR core functionlaity testcases to cover basic functionality. If functionality not working or functionality is missing testing team reject that build. if testers decided stability, they concentrate on test execution of all test cases to detect defects.
Level 1(Comprehensive Testing) :
After completion of sanity testing and possible test data preparation, testing team concentrates on execution test cases which were not executed in smoke testing on build. Test engineer prepare test log document this document consists of five types of entries. a) Pass b) Fail c) Not Executed d) Not Applicable e) Blocked
Level 2 (Regression Testing):
During comprehensive test execution, test engineers are reporting mismatches as defects into defect tracking system then assigned to developers. After receiving modified build from them, test engineers concentrate on regression testing to ensure bug fixing work and occurrences of side effects.
Level 3 (Final Regression Testing): After completion of final regression cycles, test engineers perform complete regression test cases that were identified on the final build and give a sign off opinion to test lead.