1. Isolated system: A system that can neither exchange matter nor heat with the surrounding is known as an isolated system.
For example: Water placed in a vessel that is closed as well as insulated.
2. Open system: A system that can exchange both matter and energy with the surrounding is said to be an open system.
For example: A reaction taking place in an open vessel exchanges both energy and matter with the surrounding.
3. Closed system: A system that exchanges only energy and not matter with the surrounding is said to be a closed system.
For example: A reaction taking place in a closed metallic vessel.