gnuplot changing font

I was following some instructions on using gnuplot, however the instructions for changing the font used in the graphs was wrong. Therefore I had to figure out how to achieve this.
I was looking to output some graphs to png images, so I added the following to the top of my command file used to draw the graphs

set terminal png enhanced font "<full path to font>"
set output "<filename>"

There is also an environment variable GDFONTPATH which can be set to directories containing font files, if this is used the above lines can be changed to

set terminal png enhanced font "<font name>"
set output "<filename>"