While the terms "bolt" and "screw" are often used interchangeably, they are not exactly the same thing. A bolt typically refers to a fastener with a hexagonal head that is inserted through a pre-drilled hole and secured in place with a nut. A screw, on the other hand, is a fastener that has threads that allow it to be screwed directly into a material, without the need for a nut. M8, M10, and M12 bolts are examples of bolts, not screws.