The 'PG Circuit' fonts imitates the copper tracks on the back of printed circuit boards. There are four parts to the family although you only really need to use the first of the fonts - PG Circuit 1.

The other fonts in the family represent different parts of the circuit board production process and of course, you don't have to use them if you don't need them.

As has already been stated, PG Circuit 1 produces the outlines for the copper tracks that go on the circuit board.

The next three fonts represent the holes and their associated roles as the pattern gets larger.

PG Circuit 2 represents the holes themselves. These are already in the PG Circuit 1 tracks font so you don't need it to make holes in the tracks. However, if you want to produce a mask for making holes in the circuit board, this is the font to use.

PG Circuit 3 represents the parts of the copper tracks that are tinned with solder so that they make a good connection with the component legs when they go through the holes.

You can leave it there if you want to but it is customary to put a protective layer of resin over the tracks which will both protect them physically and also protect them electrically.

PG Circuit 4 provides you with a mask that you can use to create this. Simply create a layer and then use the opacity of the PG Circuit 4 layer to remove parts of the mask where the solder has to go. Note that these masks usually have holes in them that are larger than the areas to be soldered because they are applied to the printed circuit board with a lower standard of accuracy of alignment - often via silk screen.

Note that not all printed circuit board protective resins are green. I have seen red and blue as well and as the colour lets the manufacturer know where it is easily, there is no reason why it cannot be literally any colour you like.

You can download the font from the owner's website here: http://www.billie.grosse.is-a-geek.com/resources-03yd.html