There are Triloka, Saptaloka, Chaturdshaloka – 3, 7, 14 planes/realms (Loka)
Netherworld, Earth, Heaven – Patala, Bhuloka, Svarloka.
Earth, intermediate realm, Heaven – Bhuloka, Bhuvarloka, Svarloka (together also called Vyahriti).
SAPTALOKA – Seven higher planes/realms
Svarloka, Satyaloka, Tapoloka, Janaloka, Maharloka (Heaven)
Bhuvarloka (intermediate realm)
and seven nether planes/realms
Patala, Atala, Vitala, Nitala, Rasatala, Mahatala, Sutala.
Together they are CHATURDASHALOKA.
In addition there is Naraka, the Hades, with different areas from 4 to 28 and different names depending on the Purana.