What is meant by Arudha Lagna, Arudha Pada, Graha Arudha, and Bhava Arudha?

There are many systems in astrology, e.g., Vedic astrology, K.P. astrology, Jaimini astrology, etc. Among them, the concept of Arudha Lagna, Arudha Pada, Arudha Graha, and Bhava Arudha belongs to Jaimini astrology. In a birth chart, the ascendant (Lagna), planets, and houses represent reality, whereas Arudha means the reflection of those things visible in society/the world. For example, Lagna means how you actually are, whereas Arudha Lagna means how the public/community perceives you.

For example, when Lagna is weak (degree-wise weak), people perceive you as a simple/weak person, but if that same person's Arudha Lagna is strong, people can perceive such a person as knowledgeable, influential, and prestigious. Arudha Pada is evaluating which house in the horoscope it corresponds to. When the Arudha Pada is strong, the person's influence regarding matters related to that house becomes visible among the general public.

Arudha Graha means the external influence of a person related to a planet, which is prominently visible in society. Similarly, Bhava Arudha means your image held by people associated with that house regarding matters of that house.