Let (X, G) be a G-metric space, and let > 0 be given, then a set
A ⊆ X is called an -net of (X, G) if given any x in X there is at least one point a
in A such that x ∈ BG(a, ), if the set A is finite then A is called a finite -net of
(X, G). Note that if A is an -net then X = ∪a∈ABG(a, ).