Perfect! Another interesting function that returns a geometry is
ST_Buffer(geometry, distance). According to the PostGIS documentation, this function returns a geometry that represents all points whose distance from this geometry is less than or equal to 'distance'. Sounds complicated? It's actually quite simple! Take a look:
In simple terms,
ST_buffer creates a bounded region called a "buffer around a given geometry, where all points on the edges of the buffer are guaranteed to be 'distance' away from a given geometry. Take a look:
The query above returns a buffer of 50 meters around each ATM in San Francisco.