Final answer:
To fasten or align two pieces of material, the use of a pin that fits into a corresponding hole is common, much like fitting pegs into holes in a children's toy or using a mortise and tenon joint in carpentry.
Step-by-step explanation:
To fasten or align two pieces of material, you can use a pin, which is a piece that fits into a corresponding hole. One familiar example of this concept is a children's toy where a square peg fits through a square hole and a round peg fits through a round hole. In engineering contexts, especially in carpentry, a joint formed by inserting a projecting point on one piece of wood (tenon) into a hole (mortise) in another piece is known as a mortise and tenon joint. Additionally, achieving a tight fit between a metal peg and a metal hole can be accomplished by precisely manufacturing the two components to complement each other closely.