Fireworks have been around for over a 1000 years, originating in China. But there is a lot more behind fireworks then simply just lighting the ignition and watch the firework zoom upwards and explode in various different patterns and colours.
Scientist can use various expensive machinenry to test mysterious compounds such as using mass spectroscopy or gas/liquid chromatography, but sometimes all they need to do is set fire to it and observe what happens. Different metals,when burnt, will give off different colours, as electrons get excited and change energy levels giving off different wavelengths of light. This allows us to make fireworks with specific colours. You may have to look at this at GCSE and/or A-level Chemistry.
Although fireworks are great to look at, always remember that safety is your priority as these are just fancy controlled explosives.
How many times does the work “fireworks” appear?