Spray painting is a painting technique where a device sprays a coating (oil based, water based, paint, ink, varnish etc.) through the air onto a surface. It can be applied directly from a can or with an air gun. The most common types employ compressed gas (usually air) to atomize and direct the paint particles. The air spray type (spray paint from can belongs to this type) has lower pressure, generates more atomization of paint in the room and requires better safety equipment. The airless type has higher pressure and it generates less atomization being more safe for the person who applies it.