The difference between bolts and screws lies in two aspects: one is the shape, the stud part of the bolt is strictly required to
be cylindrical, used to install the nut, but the stud part of the screw is sometimes conical or even with a tip; the other is
Using the function, the screw is screwed into the target material instead of the nut. In many occasions, the bolts also work
individually, and are directly screwed into the pre-drilled threaded hole, without the need for a nut to cooperate with it. At
this time, the bolt is classified as a screw in terms of function.