How to change login password

As per topic, how do I change my login password?
I've looked through the profile, but don't see an option to change password.

Click on "Main Site" in the grey band at the top of the window, then click on "Profile".

Thanx!

Sorted.

after clicking Profile then what should i do to change login password?

Click where it says 'change' next to the four asterisks representing the password.