Every year on the 4th of July, fireworks light up the sky with giant bursts of color and patterns. Today, fireworks are so advanced, they turn into shapes like hearts, stars, and even smiley faces. But ever wonder how they do that? Fireworks, also known as pyrotechnics in the industry, are older than the American Revolution itself.
They have advanced so much that now we have brighter colors, explosions timed to music, and shapes and patterns that wow crowds of all ages. But those shapes don't make themselves. Here's how it works.