The word "heaven" is used in the English translation of the Arabic word سماء (Samaa'a). The plural is سماوات (Samaawat), cognate of Hebrew שמים (Shamaim), which translates as "sky" in Modern Arabic.
The seven heavens are the seven layered realms of the spiritual upper world where generally angels and other spiritual beings such as Paradise and Hell and the souls of the prophets exist. The seven heavens are part of Al-Ghayb (Arabic: الغيب The Unseen), the occult or unseen universe in Islamic cosmology as opposed to Al-Shahadah (Arabic: الشهادة The Seen), the universe we know. Some scholars have said that the original meaning of the Arabic word سماوت is the hypothetical multiverse or "worlds of space and time" and not "sky" as is used in Modern Arabic.
The Qurans and numerous Hadithes record that Muhammad visited each of the seven heavens on his Mi'raj. There he met Adam, Īsā and Yahya, Yusuf, Idris (considered by most scholars to be Enoch), Harun, Musa and Ibrāhīm in the first to the seventh heaven in the mentioned order. According to Islamic tradition, God instructs Muhammad in the Seventh Heaven that Muslims must pray fifty times per day; however, Moses tells Muhammad on his descent that it is very difficult for the people and urges Muhammad to ask for a reduction, until finally it is reduced to five times per day. Shias additionally believe that the fourteen Infallible Ones also visited the seven Heavens.
Seven Heavens in the Qur'an
The Qur'an mentions the existence of seven heavens:
See you not how Allah has created the seven heavens one above another, and made the moon a light in their midst, and made the Sun a Lamp?(71:15-16)
Blessed is He in Whose Hand is the dominion; and He is able to do all things. Who has created death and life that He may test you which of you is best in deed. And He is the Almighty, the Oft-Forgiving; Who has created the seven heavens one above another; you can see no fault in the creation of the Most Gracious.(67:1-3)
Names of Seven Heavens
According to Shi'ite sources, a hadith from Imam Ali mentions the name of the seven heavens as mentioned below:
1. Rafi' (رفیع) the least heaven (سماء الدنیا)
2. Qaydum (قیدوم)
3. Marum (ماروم)
4. Arfalun (أرفلون)
5. Hay'oun (هيعون)
6. Arous (عروس)
7. Ajma' (عجماء)
Seven Earthes in Quran
... There are seven earths in Quran, according to Muhammad ibn 'Abd Allah al-Kisa'i:
The first is called Ramaka, beneath which is the Barren Wind, which can be bridled by no fewer than seventy thousand angels. With this wind God destroyed the people of Ad. The inhabitants of Ramaka are a nation called Muwashshim, upon whom is everlasting torment and divine retribution.
The second earth is called Khalada, wherein are the implements of torture for the inhabitants of Hell. There dwells a nation called Tamis, whose food is their own flesh and whose drink is their own blood.
The third earth is called Arqa, wherein dwell mulelike eagles with spearlike tails. On each tail are three hundred and sixty poisonous quills. Were even one quill placed on the face of the earth, the entire universe would pass away. The inhabitants thereof are a nation called Qays, who eat dirt and drink mothers' milk.
The fourth earth is called Haraba, wherein dwell the snakes of Hell, which are as large as mountains. Each snake has fangs like tall palm trees, and if they were to strike the hugest mountain with their fangs it would be leveled to the ground. The inhabitants of this earth are a nation called Jilla, and they have no eyes, hands or feet but have wings like bats and die only of old age.
The fifth earth is called Maltham, wherein stones of sulphur hang around the necks of infidels. When the fire is kindled the fuel is placed on their breasts, and the flames leap up onto their faces, as He hath said: The fire whose fuel is men and stones (2:24), and Fire shall cover their faces (14:50). The inhabitants are a nation called Hajla, who are numerous and who eat each other.
The sixth earth is called Sijjin. Here are the registers of the people of Hell, and their works are vile, as He hath said: Verily the register of the actions of the wicked is surely Sijjin (83:7). Herein dwells a nation called Qatat, who are shaped like birds and worship God truly.
The seventh earth is called Ajiba and is the habitation of Iblis. There dwells a nation called Khasum, who are black and short, with claws like lions. It is they who will be given dominion over Gog and Magog, who will be destroyed by them…
Hinduism also has the concept of seven heavens(Svarga). According to the Puranas and the Atharvaveda there are fourteen worlds. There are the seven higher ones (the heavens), called the Vyahritis (Sanskrit: व्याहृति)
The names of the seven lower ones (the underworlds) called the Patalas (Sanskrit: पाताल) are: Atala (अतल), Vitala (वितल), Sutala (सुतल), Rasaatala (रसातल), Talataala (तलातल), Mahaatala (महातल), Patala (पाताल).
^Vuckovic, Brooke Olson (December 30, 2004). Heavenly Journeys, Earthly Concerns: The Legacy of the Mi'raj in the Formation of Islam (Religion in History, Society and Culture). Routledge. ISBN978-0-415-96785-3.