Step 620–25 minutes
Input / Output (I/O)
Programs are useless if they can't interact with the world. I/O is how a program gets data (Input) and sends data out (Output).
Common I/O devices include the keyboard, mouse, monitor, storage disks, and network cards.
The I/O Path
Your Program
System Call
Operating System
Driver
How Programs Wait
PROGRAM
The program stops execution entirely until the I/O operation (like reading a file) is finished. It's simple but can feel slow.