i. Open System - Here the system boundary is like energy and matter can enter or leave the system freely. Infect the system boundary here is imaginary.
ii.Closed System - Here the system boundary like only energy but not matter may leave or enter freely. The system boundary is known as diathermic.
iii.Isolated System - Here the system boundary like neither energy nor matter can leave or enter the system. The system boundary is known as adiabatic