How do I change my units?

I usually use inches, but I have a job where it would be more convenient for me to have pixels. What’s a fast way to change the units?

Just make sure that your Rulers are turned on—Cmd R (Cntl R on PC)—and right click on the ruler itself (Control click if you don’t have a right button) and you will see a list of available units. Just scroll to the one you want.