Q: What is Bug Tracking?
A1: A bug tracking system is a software application that is designed to help quality assurance and programmers keep track of reported software bugs in their work.
OR
A2: Bug Tracking system is a centralized system used to Report bugs and keep the track of all the bugs found during execution of testing also it helps in knowing the status of the bug, the concerned person is intimated with the bug status.

Q: Explain defect life cycle?
A: Defect life cycle:
1. If the bug is new then open it.
2. Assign it to tester.
3. Retest it.
4. If still have not resolved reassign it.
5. Retest it.
6. After resolving, close it.