Don't Panic! $k$-Tensors are quite different to tensor products and I also won't write down any commutative diagram, I promise! Instead, $k$-tensors are used to answer questions in extremal combinatorics using linear algebra. We are going look at a beautiful proof for a surprising fact in extremal combinatorics and then try to generalize the main idea, which will lead us to $k$-tensors and its slice rank.