What is difference between "is" and "=="?

Question

Can anyone explain what is difference between "is" and "=="?

example:

x = 2
if x is 2:
do something

OR

x = 2
if x == 2:
do something

Answer 1

the == operator compare the values
is operator check if the referenced objects are the same.
see this discussion: http://stackoverflow.com/questions/132988/is-there-a-difference-between-and-is-in-JUMP_LINK__&&__python__&&__JUMP_LINK