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Homotopy groups are tools used in [[algebraic topology]] to classify [[topological space]]s.  The different ways to map an ''n''-[[sphere]] continuously into a given topological space are divided into equivalence classes, called '''homotopy classes'''.

Homotopy groups are tools used in [[algebraic topology]] to classify [[topological space]]s.  The different ways to map an ''n-sphere'' continuously into a given topological space are divided into equivalence classes, called '''homotopy classes'''.