These are important concepts used in Vedic Astrology.
Natural Atmakaraka is the Sun for all individuals. Apart from this, we have 8 Chara Karakas (variable significators), representing various functions, namely:
1. Atma karaka (AK) – Self
2. Amatya karaka (AmK) – Minister
3. Bhratri karaka (BK) – Siblings
4. Matri karaka (MK) – Mother
5. Pitri karaka (PiK) – Father
6. Putra Karaka (PK) – Children
7. Jnaati karaka or Gnaati karaka (GK) – Rivals
8. Dara karaka – Spouse
In any person’s horoscope, list the degree advanced by one of the 8 planets – Sun to Rahu. In the case of Rahu alone, subtract the degree traveled within the sign from 30 degrees (since it is moving in the reverse direction). Arrange these angular degrees traveled in descending order. The planet which has moved the highest degree within a sign is called Atma karaka.The second highest is called the Amatya karaka.
Atma karaka throws more light on the Atma (inner self) of the native. Amatya karaka has to do with the profession of the native.