ELI5: Explain Like I'm 5

Matrix multiplication

Matrix multiplication is like a puzzle. You have two matrices, which are groups of numbers like a table. Each matrix is kind of like a picture frame, where the numbers are like different colored tiles. To make the new picture, you line up the two frames, so the tiles line up with each other. Then, you count up each tile to find the number for the picture in the new frame.
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