Q: What did the mouse say to the keyboard?
A: You are really my type!

Explanation: Computer humor!

A mouse can be a small animal or a device that helps you work with a computer.  In this joke, I am talking about the computer mouse, so picture a computer mouse talking to the computer keyboard.  

And what do you do with a keyboard?  You type on it to enter information into the computer.  (Did you know that there are one-handed keyboards?)

“You’re my type” is an idiom that means that I like you, or that we will get along well together.

This joke is funny because it plays with the word type and the idiom “you’re my type.”

If you would like to practice typing, here is a video to get you started: