What are Chilate Ligands and Chilation?? answer plzzzz fast

When a di or polydentate ligand uses its more than one donor atoms to bind with metal ion or atom & form a ring like structure (commonly 5,6 even 7 membered) within the coordination entity then the ligand is called chelate ligand and the process of formation of chelate compounds is called Chelation.Some chelate ligands are ethylenediamine, glycinate ion, oxalate ion etc.Chelate compounds are more stable than coordination compounds formed by monodentate ligands as the entropy of the system increases.The stability of chelate compounds increases with the dentesity of the chelate ligand.