Why can't the Ctrl key cross the road? Because it is an 8-lane highway.
Ctrl Key's Roadblock
Explanation
Explain Bear
Listen up, buttercup! The joke is all about wordplay. See, the "Ctrl" key sounds like "control." And what do you need when crossing a big, bad 8-lane highway? CONTROL! It's funny because it's so obvious... or maybe not for you, I guess.