The two Voronoi Textures are not exactly the same, but in the old days, you would change between Intensity (‘black dots’) and Cells (colored).
Now there are two outputs that handle that; Distance and Color:

There are a few more options for the Voronoi now
Play with it and/or read the manual: https://docs.blender.org/manual/en/2.81/render/shader_nodes/textures/voronoi.html?highlight=voronoi