A

messaging app is waiting for a network packet to arrive.

A

database server is executing a complex SQL query right now.

A text

editor is actively rendering text on the screen.

A

backup process has requested a disk write and is waiting for it to finish.

A

video game is waiting for the player to click the mouse before continuing.

A

compiler is currently translating source code into machine code on the CPU.

A web

browser was preempted by the scheduler (time slice expired) and is waiting to

resume.

A

music player is in the run queue, but another application is using the CPU.