What are Vector Tiles?

And how do they differ from raster tiles?

vector tile

Same benefits as raster tiles: caching, scaling, moving map around

Additionally:

Styling: vectors can be styled when requested

We can change the display characteristics of points, lines, polygons
Not pre-rendered

Size: vector tiles are really small, which makes them high resolution and fast!

Only 20-50% the size of equivalent raster tiles