What is major difference between Python 2 & Python 3 ?

Answer 1

for beginners, it's the difference between print "a" vs print("b") . there are also other changes, but generally you won't encounter them often

Answer 2

The biggest difference is that in Python3 everything is an object. No more 'statements', only objects. Nah, ok, there are also the reserved keywords. But apart from that -- all objects.

That may cause backwards compatibility problems - codes and modules may not work properly, unless handled adequately.

Python3 also comes with lots of new datatypes and modules embedded inside. Plus ot is still being developed, while Python2 is only under maintenance for a few years.

Answer 3

http://sebastianraschka.com/Articles/2014_python_2_3_key_diff.html