What would you do if you had a time machine?

I will go to my college days and i wll enjoy more than tat i enjoyed previously,and if at the time of exams i will go forward by skipping the exams time.

I'd visit the future, then try to bring back technology for producing clean energy, clean water and growing nutritious food in less-favorable conditions. You know, stuff that could save the world, feed the hungry and all? I'd need funding, so I'd use the time machine to see what investments would be most profitable. And even though I'd be worried about tinkering with the past a lot, if I could come up with a way of stopping the 9/11 terrorist attacks, I'd do it in a heartbeat.

What are Time Machines. The Clocks are not time machines ? What is the concept ?

if i had a time machine i think i travell in time to find out how the world has been created and to find out many others secrets of this world. in the future i don't think i'll travel because if i'll find out what will hapens and the life wouldn't be interesting.