During my latest project, I was given a shapefile and I was told to make a web GIS interface to handle it. I found a Node.js plugin to open the file and load the GeoJSON data onto a Google Map, but then I noticed something was odd: the coordinates were very big numbers, definitely not longitude/latitude pairs.

After installing a GIS software and a lot of googling I found out about the existence of many standards for coordinate values.

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