These classes are relevant to threaded applications.
| QMutex | Access serialization between threads |
| QMutexLocker | Convenience class that simplifies locking and unlocking mutexes |
| QReadLocker | Convenience class that simplifies locking and unlocking read-write locks for read access |
| QReadWriteLock | Read-write locking |
| QSemaphore | General counting semaphore |
| QThread | Platform-independent threads |
| QThreadStorage | Per-thread data storage |
| QWaitCondition | Condition variable for synchronizing threads |
| QWriteLocker | Convenience class that simplifies locking and unlocking read-write locks for write access |
