Spontaneous and Non spontaneous process

Spontaneous process :-

All natural process is spontaneous process. Spontaneous process means without any external force such as water flow downward but if you want to reverse it then external force required for this process.

Example : -   Water flow downward, Evaporation of water

NonSpontaneous process :-

Such process which can not be done without any external force or In other word That process which is done by external force is called nonspontaneous process.

It require some external force to complete.

Ex : - Photosynthesis

Photosynthesis processed in the presence of light.