What causes things to explode?

What makes things explode? Why do some things like a firework blow up with a bang? Which everyday items are unstable enough that they can be explosive? Plus get free kid-friendly activities at www.WhoSmarted.com ! See omnystudio.com/listener for privacy information. See Privacy Policy at https://art19.com/privacy and California Privacy Notice at https://art19.com/privacy#do-not-sell-my-info.