A Topological Space is compact if every open cover of has a finite subcover. In other words, if is the union of a family of open sets, there is a finite subfamily whose union is . A subset of a Topological Space is compact if it is compact as a Topological Space with the relative topology (i.e., every family of open sets of whose union contains has a finite subfamily whose union contains ).

© 1996-9

1999-05-26