A choropleth map shades or pattern areas in a map in proportion to the measurement of the statistical variable being displayed in the respective area.
Tile servers
The zoom level determines the number of tiles required to map the entire World. The formula is 4 ^ $zoomLevel (for example zoom level 0 has one tile, zoom level has 64 tiles etc.)
Tiles are 256x256 pixels (Mapbox GL: 512x512 pixels).
Ramer–Douglas–Peucker algorithm
The Ramer–Douglas–Peucker algorithm is an algorithm that transforms a given curve composed of line segments (aka a polyline) to a similar curve with fewer line segments (and points).