Take a look at this picture:
The red lines inside a glyph is what I'm referring to as "central" or "pen" strokes. Imagine you drawing the letter using a pen, so you only have thin strokes which define a general shape of a letter instead of wider inked areas which font glyphs typically have.
What is the proper name of this type of strokes? I've looked through a lot of "font anatomy" illustrations, and none of them mention this.
Are these lines used in font design? Maybe when you create a digital font, you could start with those strokes and then add modulation. For fonts like Comic Sans it may be even sufficient to just use these strokes with proper line width.
If the answer for the previous question is "yes", do any font formats store this information along with glyphs? If they do, what it's used for? I guess, for some fonts this can be used to dynamically create glyphs with different thickness.