Have you ever seen a really big tower or an archway that has a cool shape on top of it? That's called a pylon! Think of it like a giant decoration that helps make buildings or gates look really awesome.
In ancient times, people would build big structures with these tall and pointy things on top to show how important their buildings were. Imagine a castle or a temple with a big pylon on top - it would look really cool, right?
But nowadays, people still use pylons in architecture. You might see them at the entrance of a big university or on a bridge. Pylons can have all sorts of shapes and sizes, but they all help to make buildings or gates look really special and important.