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Ask me anything about your lessons or your code.
“What is a port?” · “Why is my code erroring?”
A GIS is software for data that is tied to places. It answers questions a spreadsheet cannot, because it knows where every record sits on the Earth.
What GIS Is and Why It Matters
A GIS is software for data that is tied to places. It answers questions a spreadsheet cannot, because it knows where every record sits on the Earth.
Vector and Raster: Two Ways to Store the World
Every geometry in a GIS is built one of two ways, as exact shapes made of coordinates or as a grid of measured cells, and the choice decides what questions the data can answer.
Coordinate Reference Systems and the Shape of the Earth
A pair of coordinates only means something once a coordinate reference system says what model of the Earth those numbers are measured against.
Why Every Flat Map Lies
A projection squashes the round Earth onto a flat plane, and the math forces a choice about which property to keep true and which to sacrifice.
The Data Table Behind the Map
Every layer carries a plain data table alongside its shapes, and an attribute join attaches outside data to that table by a shared key, not by location.
Scale, Resolution, and Trusting Your Data
A dataset's scale and resolution set a hard ceiling on what it can honestly answer, and the most detailed data available is not always the right data for the question.