Boundary (topology)
DIVIDING LINE BETWEEN TWO AREAS OR SETS OF POINTS IN A TOPOLOGICAL SPACE; DIFFERENCE BETWEEN THE CLOSURE AND THE INTERIOR
Boundary point; Boundary points; Frontier (mathematics); Boundary component; Boundary set; Frontier (topology); Boundary (algebraic topology); Boundary of a set; Boundary Functions; Boundary (mathematics); Topological boundary; Boundary (geometry)
In topology and mathematics in general, the boundary of a subset of a topological space is the set of points in the closure of not belonging to the interior of . An element of the boundary of is called a boundary point of .