What is a Hasse diagram? How is it constructed?

Question

What is a Hasse diagram? How is it constructed?

Answer 1

What is a Hasse diagram?

Hasse Diagram named after Helmut Hasse (1898–1979)) is a simple picture of a finite partially ordered set, forming a drawing of the transitive reduction of the partial order. Concretely, one represents each element of S as a vertex on the page and draws a line segment or curve that goes upward from x to y if x < y, and there is no z such that x < z < y.

How is it constructed?

By defining its ordered sets.