Why is my pause button always gray? For the system to gain enough information to pause/unpause the application you need to enable super user mode. Once enabled selecting an applicaiton you own from the list should cause the pause button to become active. How do I pause a process?

If you want to pause a process you can click the pause process button.

 How do I unpause a process?

If you want to unpause a process you can click the unpause process button.

 How does pause/unpause work? Pausing and unpausing a process uses unix signals, specifically the STOP and CONTINUE signals to controll the process execution. When you stop the process you send it the STOP signal, to start it you send it the CONT signal. Stopping a process tells the operating system to cease execution of the process exactly where you left off. When you start it again it picks up where it was. What are the dangers of pausing a process? Pausing a processes stops its execution. This is normally fine for something like a large Bryce render. However, if you are using iDVD a lot like I do you might be tempted to pause it. This is fine, unless it is in the middle of the burning phase. A general rule of thumb is that an application that isn't writing to a removable drive or the internet is fine to pause. One that is will likely have problems if you pause it.