What is QGIS?
QGIS is an open source GIS application for creating, editing, visualizing, and analyzing geospatial data.
Availability: Free (download here). Mac OSX, Windows, Linux
The QGIS website will have two versions of QGIS available for installation for Window, Mac, and Linux: a long-term release version (the most stable version of the software) and a current version (the newest and richest version of the software). Either version is fine to download.
New versions of QGIS are released regularly. If there's a new release, you will be alerted by a banner at the bottom of the start screen in QGIS.
See below for videos instructions for how to download and install QGIS 3.x for Mac and Windows 10.
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