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Table of Contents
QGIS
First, let's get this over with and go with the basics.
Shape Files
What are shape files ? They are files that store polygons. An example of a shape is a triangle, which consists of 3 X,Y coordinates on a 2 dimensional plane. A square has 4, and so on. A state or a county can have hundreds of points. States like Colorado (basically a square)are much simpler compared to New York, New Jersey, etc.. or Wisconsin.
PUMA
The US census no longer provides information about counties. Instead they have come up with regions called PUMAs, which represent units of 100K people. In some counties that are huge (New York, Brooklyn) there are many PUMA regions in each county. In South Dakota, multiple counties are merged to form a single PUMA area.
PUMA DATA
Where can I find this PUMA data ? I downloaded it from here: https://www2.census.gov/geo/tiger/TIGER2020/PUMA/
Shapefile Files
Since each shape file corresponds to a state, I created a directory for each state and placed the assorted zip files into those directories.
For example, file “tl_2020_34_puma10.zip” will go into directory /opt/qgis/puma_2020/NJ I then proceeded to unzip each file in their respective directory.
Starting your Project
Menu –> Project –> New
Showing a map
Menu –> Web –> Quick Map Services –> OSM –> OSM Standard
You can zoom in on an area by using the scroll wheel on your mouse