In the topic of transition metals, what are the different types of ligands and what in itself, is a ligand?

Firstly, ligands are an atom, molecule or ion which can donate a electron pair (lone electron pair). In a diagram, we would show this donation of a lone electron pair to a central metal ion by using a arrow. Ligands can be monodentate, thus forming one coordinate bond per ligand. An example would be H20 or Cl-.( If unfamiliar, a coordinate bond is simply a covalent bond, except the shared electron pair is coming from only one of the bonding atoms.) Another type of ligand is a bidentate ligand which has two atoms with lone electron pairs and can form two coordinate bonds. An example of such would be the enthanedioate ion (C2O4-). Lastly, we have one more type of ligand, that being a multidentate ligand and can form 6 coordinate bonds per ligand. An example of such would be EDTA 4-.