This typo came across MRP’s desk recently:
Using their curser, students can easily change variables such as the type of display and the scale of the graph.
Okay, here’s the deal: When you are talking about someone who put a hex on you, that’s a curser. When you are talking about the blinky thing on your computer screen that tells you where to type, that’s a cursor.
Unless you’re Harry Potter, in which case maybe you do use a curser to help you do your math homework.