How to change the editor's font?

[ghost]

I wanted to change it to something else but I can't find where the setting is.

[fredvs]

The font of editor is defined by the project options:

If you prefer to have your own config for all projects, independent of the options of the project, go to menu / Settings / Extra settings and, in right side of window, select in Source Editor: "X Use those options instead of project options".
And set all the values that follow like you want.