Pointless topology

Pointless topology, also known as "point-free topology," is a branch of topology that focuses on the study of topological structures without reference to points. Instead of using points as the fundamental building blocks, it emphasizes the relationships and structures formed by open sets, closed sets, or more general constructs such as locales or spaces. In typical point-set topology, a topological space is defined as a set of points along with a collection of open sets that satisfy certain axioms.