What is the difference between homologous structures, vestigial structures, and analogous structures?

Homologous structures are anatomical features that have a similar structure or origin, even if they perform different functions. For example, the human arm, the bat wing, and the dolphin flipper are all homologous structures, as they all have the same basic bone structure, despite their different functions.Vestigial structures are anatomical features that have lost their original function through evolution. For example, the human appendix is a vestigial structure, as it no longer serves a useful function in the body.Analogous structures are anatomical features that perform a similar function, but have a different structure or origin. For example, the wings of a bird and the wings of an insect are analogous structures, as they both allow the organism to fly, but they have very different structures.In summary, homologous structures have a similar structure or origin, vestigial structures have lost their original function, and analogous structures perform a similar function but have a different structure or origin.