Communicable diseases transmit from one person to the other, but non-communicable do not.
The main cause of communicable diseases is germ or parasite, whereas the cause of a non-communicable disease is our unhealthy lifestyle.
The communicable diseases are transmitted through physical contact, like insect bites, air, water, etc. but non-communicable diseases are not transmitted except through heredity.
The communicable diseases are acute and have quick recovery but the non-communicable diseases are chronic and have no or longer recovery.
Diarrhoea, dysentry, cholera, gonorrhoea, etc. are communicable diseases where cancer, diabetes, malnutrition, anaemia, etc. are non-communicable diseases.