Astrology can be very broadly classified into the following
SAMHITA
It involves prediction for the masses such as forecast of earthquake or cyclone or any natural calamity, change in governments or economic trends, stock market among others.
SIDHANTHA
It is also known as the Ganita or Tantra. It involves all the mathematical aspects and is further split into Surya, Romaka, Paulisha, Paitamaha, Vasisthla
HORA
It deals with both Natal chart which gives prediction on all aspects of the individual. Its also known as Jataka. Hora also deals with Muhurtha which is used for prediction of outcomes for daily events which hold a huge importance such as wedding or starting a career etc.,