Heaven is also known as Paradise. It goes by the Islamic name of Jannah. There are many levels of Paradise depending on how righteous a person is on Earth. The highest level that all Muslims are encouraged to ask for is Jannatul Firdaus. Like with other aspects of the unseen, Muslims are obligated to believe in Heaven in order to complete their faith.
The bounties and beauty of Heaven are immense, so much so that it is beyond abilities of mankind's worldly mind to comprehend.
However, Allah, in his Mercy, has given us descriptions of what Heaven is like as an incentive for us to strive to please Him and earn His ultimate reward – which is a place in Heaven.
Forever – Paradise is forever. Once a Muslim reaches Paradise, he will not want to be anywhere else and he will live there for eternity.
Wealth – there will be an abundance of wealth and beauty in Paradise. Allah says in the Quran, Surah Al Kahf, verse 31: “For them will be Gardens of eternity; beneath them rivers will flow; they will be adorned therein with bracelets of gold, and they will wear green garments of fine silk and heavy brocade. They will recline therein on raised thrones. How good [is] the recompense! How beautiful a couch [is there] to recline on!”
Eligibility – whoever has worshipped no one but Allah is qualified to enter Heaven. This includes the followers of past prophets such as Noah, Abraham, Moses, Jesus, etc who adhered to their true teachings and worshipped Allah without partners. However, according to Islamic teachings, the followers of Muhammad (may Allah's peace and blessings be upon him) will be more abundant in Heaven than those of other prophets.
The unknown – what bounties of Paradise cannot be comprehended when compared to worldly riches. Allah has told us many things about Paradise, but in a narration in Saheeh Muslim, the Prophet said: “Never mind what Allah has told you; what He has not told you is even greater.”