What organs are called homologous, similar and rudimentary? Give them examples

Homologous organs (from the Greek. Homologia – consent) have a similar structural plan, develop from the same germinal buds, perform both similar and different functions in organisms. An example of homologous organs is limbs. representatives of various orders of mammals that developed in the process of evolution from the same germinal embryos and adapted to perform various functions.
Similar organs (from the Greek. Analogia – lobodia) perform the same functions, but do not have a single structural plan and develop from different germinal buds. So, the protection against eating – spines of barberry are mutated leaves, and the similar thorns of hawthorn – mutated shoots.
The rudimentary organs (from lat. Rudimentum – an embryo) lost their initial meaning in the process of evolution. They are laid in the period of embryonic development, but do not fully develop. For example, rudiments of the pelvic bones in the skeleton of a whale confirm the fact of the origin of this animal from ancestors with limbs.

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