A firecracker is a pyrotechnic product that is used to create a sound effect and may have an accompanying light or whistling effect. The main purpose of firecrackers is to generate a loud sound effect, which is measured in decibels at a certain distance from the firecracker. Firecrackers come in various shapes and sizes and may have various additional effects such as a light flash, whistling, etc.

Firecrackers up to category F3 are freely available in the Czech Republic for persons over 21 years of age and it is not necessary to have a fireworks launcher's licence to use them. These firecrackers are classified as low-risk explosives and may only be used in accordance with current regulations. The instructions for use and all safety precautions must be strictly followed to minimise the risks when handling firecrackers.