A molotov cocktail is a weapon that people make from things they have in their homes. It's like a homemade bomb that can set things on fire.
First, they take a glass bottle or a jar and fill it with gasoline or another flammable liquid. Then, they take a piece of cloth or a sock and soak it in gasoline.
After that, they stuff the cloth into the opening of the bottle and light it on fire. Then, they throw the bottle at something they want to burn or destroy, like a car or a building.
It's very dangerous to use a molotov cocktail, and it can hurt people or start a huge fire. That's why it's illegal in many places and should never be used.