It’s pretty special to experience fireworks. Pyrotechnic explosions. Blasts of light and colors in the night sky. Invented in the 10th century by the Chinese, they knew they were onto something that was certain to be a hit. So they pretty much kept it a secret (along with gunpowder) for a few hundred years. Fireworks have always been part of festivals or celebrations which adds to their emotional impact.
Keeping the shutter delayed slightly adds to the depth of the capture; instead of just capturing a moment in time. If you get a chance to photograph these outbursts, try to locate over water for added drama. The resulting reflection is far less predictable than the actual fireworks and doubles the display.