I'm using Ubuntu for the first time and Python as well.

There are 2 versions of Python installed by default

$ python3 --version
Python 3.5.2

$ python --version
Python 2.7.12

I don't understand why two versions of the same software are installed.

  • 1
    TL;DR: python2 and python3 are not the same. The differences are large enough that most software written in python2 hasn't been ported to python3. The Python people recommend that python remain python2. Hence, both.
    – muru
    Oct 26, 2017 at 8:45

1 Answer 1


Many python application were built using the earlier versions of python and will not work with new python versions. So on Ubuntu these different versions are installed to meet the different requirements of certain programs.

Remember libraries are built using specific python versions so if one is using such a library then the particular python version for that library to work will have to be installed.

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