Why do screws have so many Drive types?

Why do screws have so many Drive types

一、What are the types of screwdrivers?

Types of Screwdriver.

Flat Head (or Slotted Head) Screwdriver.

Phillips Screwdriver.

Pozidriv Screwdriver.

Torx Screwdriver.

Hex Screwdriver or Hexagon Screwdriver.

二、Why are there round, cylindrical and conical "Drive types"?

The first  (with or without nuts): screws, bolts

The second (convex but not protruding): countersunk head, unsunk head

The third：cross, slot, inner hexagon, hexagon, special shape

Bolts, nuts, and connection diagrams

三、Socket screws, bolts and allen wrenches

A lot of hexagon socket screws are used in bicycles