Why do I need to use pip3 but not pip

[Cameron Simpson]

On 30Mar2019 13:50, Arup Rakshit <ar at zeit.io> wrote:
>When I read this https://pip.pypa.io/en/stable/installing/ it says I 
>have the pip installed when I installed the python from official doc. 
>But when I run the `pip` command from shell, I get error, but pip3 
>works.
>
>~/python_playground
>▶ pip --version
>
>zsh: command not found: pip
>
>~/python_playground                                                                                                                                           ⍉
>▶ pip3 --version
>
>pip 18.1 from /Library/Frameworks/Python.framework/Versions/3.7/lib/python3.7/site-packages/pip (python 3.7)

Ok, you've installed python 3 on a Mac.

Historically most systems have shipped with python 2 (from the OS 
vendor, which is Apple in your case), and the "python" command invokes 
Python 2.  So python 3 is installed as the "python3" command to avoid 
confusion.  The "pip" command from your python 3 install looks like it 
is also installed as "pip3" to avoid confusion.

>Do I always need to install using pip3 program then?

Yes, that is correct for this particular install.

Cheers,
Cameron Simpson <cs at cskk.id.au>