this just reminded me of something my mum said the other day. i was doing some work on her smart car to get it ready for its MOT.
she said to me do i need to top up the brake fluid. i said no its fine why did you ask that. and she said coz i wasnt sure if i had used it all yet.
i said what, what you on about. she said you no, the brake fluid that gets sprayed on the brake disc to cool them down everytime you break

i then had to explain to her what brake fluid actually does. she still didnt quite get it
