A Changeling and a Shapeshifter (or Shapechanger) are two similar classes with the ability to transform into other beings. Changelings are humans with the power to transform into animals, while Shapeshifters are animals who can 'shapeshift' into humans. The notable Changelings in the Aveyond series are Ean and Rayina while Shapeshifters are Frederick and Yvette.
Sometimes, Changelings are not able to turn into animals without figurines. In Aveyond 2, Ean uses figurines to transform into different kinds of creatures and to turn back into an elf.