What is homologous organ with examples?

Homologous organs are structures in different species that share a common ancestry but may serve different functions. For example, the forelimbs of humans, whales, and bats are homologous; they all have a similar bone structure but are adapted for grasping, swimming, and flying, respectively. This similarity reflects their evolutionary origins despite their different uses. Other examples include the wings of birds and the flippers of penguins, which also demonstrate this concept.