What Does Hang Mean?
A hang is an event where a computer becomes unresponsive due to either a program or the system itself becoming unresponsive and no longer taking input. It is a blanket term for unresponsiveness, be it a small application or process, the operating system itself or a piece of hardware being unresponsive, in which case the only solution for it is killing the process, or in the case of a hung OS or unresponsive hardware, a hard reboot.
A hang is also known as a hangup.
Techopedia Explains Hang
Hangs have a variety of causes, from software encountering an error that it cannot handle, simple lack of resources, which means the system is actually just waiting, to more serious systemic problems such as driver incompatibility or hardware malfunction. Most hangs are minor and usually resolve themselves, especially if it is only a resource issue, meaning it only appears to be hung because it is waiting for a resource such as memory or CPU time.
Hangs on the operating system itself suggest a deeper problem; it could be that there are various conflicts with the system drivers, discrepancies in the system registry or even a virus or malware infestation affecting the normal operations of the OS. Hardware-related hangs might be caused by faulty drivers and other conflicts or the hardware itself may be defective. The most common hardware-related hangs and crashes are caused by damaged sectors in the memory module.