or q-tip vs. cotton swab
but you shouldn't call it a Post-it unless its an actual post-it brand sticky note. if you do you destroy the value of the brand. companies record their value of their brand on their balance sheets, when the brand becomes a genericized trademark (meaning that people refer to any brand of sticky as a post-it) then that companies is worth less. ..... its the reason that when you ask for a Coke and the restaurant has only Pepsi they have to say "we only have Pepsi." Coke invests a lot of money into preserving the value of their brand.
.... and now you know.