A trouble ticket system is a software that supports the handling and solving of problem reports from users. Any reported problem results in a "trouble ticket" which is then classified (possibly by an AI) and assigned to someone who has to do diagnosis and find a solution, supported by an integrated knowledge base. If it proves to difficult, the TT can be forwarded to a specialist.

The TTS software formalizes this process, and ensures that problem reports aren't forgotten or ignored. In many cases, the user can track the progress of "his" TT.

Bugzilla is basically a TTS, just one that's geared towards software development anstead of network management.