Polystyrene or Styrofoam cups are not biodegradable and cannot be recycled, which means that these cups contribute to landfill trash.
Plastic cups are not biodegradable either but many of them are recyclable. However, less than 1% of plastic cups ends up in recycling plants.
Disposable paper coffee cups are lined with polyethylene, a type of plastic. This coating prevents your cup from turning to mush while you enjoy your favorite coffee, but it also means these cups can’t be easily recycled.