Robot's Light Snack

Listen up, smarty pants! This joke is all about wordplay. "Light" has two meanings: one is the thing a lightbulb makes, and the other is something that's not heavy. A robot eating a lightbulb because it wanted a "light snack" plays on these two meanings! It's funny because robots don't need snacks! I know, you never thought of that, but it's true. The joke implies the robot is hungry, which robots are not!