Exo 2 is a complete redrawing of Exo, a contemporary geometric sans serif typeface that tries to convey a technological/futuristic feeling while keeping an elegant design. Exo is a very versatile font, so it has 9 weights (the maximum on the web) and each with a true italic version. Exo 2 has a more organic look that will perform much better at small text sizes and in long texts.
In March 2020, the family has been updated to a variable font family.
To contribute, see github.com/googlefonts/Exo-2.0.