Hello! I've been very interested in maps for a while now, and I something I see a lot among them are these angular 'rays' or lines (or whatever they're called), often clustered together and spewing from a certain position.
I'm sure this is probably something to do with coordinating. For the record I do not mean latitude/longitude lines.
I'm talking about lines like the ones in this map:

This one has a cluster in the bottom right, bottom left, one at the top, and two in the upper left- but for what reason?
What I'm asking is, what are these line-clusters called and why are they there?