What is exact difference between tick mark and check mark. I know about ticking something as done and marking as checked. I thing both are same but what is exact difference.
Explanatory comments are most welcome.
They are the exact same thing. Tick mark tends to be said more commonly by British people and check mark tends to be more commonly said by Americans. Additionally, as a native American English speaker, I do find myself saying "tick the box" once in a while, but at the same time I personally never say "tick mark."
See this answer for further reference.