2018/01/28 It's been almost 3 years since I wrote this article, and a new virtual environment tool has appeared, so I'd like to organize my head separate article I wrote items / 9edcc9adca302f2959c7). If you are interested in building a virtual environment, please refer to that article. 2017/10/22 masmatsum wrote an additional note. Thank you very much.

Introduction

A note that I started hearing the words pyenv and virtualenv since I started Python, and when I couldn't understand the difference at all, I was taught various things.

I added what I was taught around January 2015 today (2015/04/11) PyHack. .. Until today I didn't recognize the difference between pyenv and pyvenv.

Roughly summarized

pyenv is Python's own version control tool, virtualenv and pyvenv are Python's package management tools
pyenv cannot be used on Windows
People using Python 2 series / 3.2 series or earlier are using virtualenv
pyvenv is available in Python 3.3 and above (included from the beginning)

About each tool

pyenv

Tools for managing different versions of Python
You can specify any version you like, such as Python 2 series or 3 series, and execute it.
Not available on Windows Reference: https://github.com/yyuu/pyenv/issues/62

virtualenv

Python package management tool
Using the specified Python, you can create an environment by installing a package for each project to be created.
Used when you want to change the package to be included for each project
People using 2 series and 3.2 series or earlier are using virtualenv.
Considering various circumstances such as it is troublesome to use different tools depending on the version, it is recommended to use this for the time being even for those who are using 3.3 series or later (as of 2015/04/11) by @aodag

pyvenv

Python package management tool
Available in 3.3 series and later
3.3 series and later are included from the beginning
Using the specified Python, you can create an environment by installing a package for each project to be created.
Used when you want to change the package to be included for each project
Easy to use for those who are using 3.3 series or later because it is included from the beginning
As shown in the "Addition" below, use venv instead of pyvenv for Python 3.6 or later.

Summary

Windows users can use virtualenv or pyvenv for the time being, but for the time being, virtualenv is recommended.
If you want to use different development environments, you must use it.

bonus

I am using pyvenv because I am a person of 3.4 series or later + the first person I was taught was pyvenv.

Postscript

Starting with Python 3.6, pyvenv has been deprecated. Use python3 -m venv instead.

reference: https://stackoverflow.com/questions/41573587/what-is-the-difference-between-venv-pyvenv-pyenv-virtualenv-virtualenvwrappe/41573588#41573588 https://docs.python.org/dev/whatsnew/3.6.html#id8

Special Thanks python mini-hack-a-thon Python Mokumokukai @ Allied Architects (Ebisu) PyLadies Tokyo