What is /dev/shm and What is it Used For?

What is /dev/shm and what is it used for?

/dev/shm is shared memory. It is offered in Linux as a way for memory to be accessed simultaneously by multiple programs.

shm is also known as tempfs or temporary file storage. On Linux it will appear as a mounted file system that you can access directly. Instead of writing to a permanent storage device such as your hard drive, it writes to virtual memory (i.e., it lives in RAM). Since it is memory, anything written to this file system will be removed the next time you reboot.