Answer - Semaphore wait signal: - They can be used anywhere except in a monitor. - The wait() function does not always blocks its caller. - The signal() function increments the semaphore counter and can release a process. - If the signal() releases a process, the released and the caller both continue. Condition Variable wait signal: - It can only be used in monitors. - The wait() function always blocks its caller. - The signal() can either release a process or it is lost as if it never occurred. - On signal() releasing a process either the caller or the released continues but not both at the same time.