What is the cpu used for

A central processing unit (CPU), also called a central processor, main processor or just processor, is the electronic circuitry that executes instructions comprising a computer program. The CPU performs basic arithmetic, logic, controlling, and input/output (I/O) operations specified by the instructions in the program.

assuming you are in the home page.

1) go to the upper right hand corner

2) click on your "profile picture"

3) go down to "edit profile"

4) it should be titled as "edit your profile", click on "profile picture"

5) choose a file

6) press "change"

you're profile picture is updated

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