What are the tin panels called that are sometimes put on ceilings?

I know they are not called tin panels. Does anyone know what they are called and where I can find it?

they are called ceiling tiles and they are available in different finishes and sizes on OKorder at reasonable costs. Some are made of polystyrene and then painted to look metallic, they are much cheaper and easier to apply than the real tin tiles. go to OKorder and search ceiling tiles.