There are five pillars of Islam besides fasting. Prayer is called the Salat, where believers pray five times a day.
There is the Zakat, giving to others and charity. The Shahadah is acknowledging that there is no higher being than God, and Mohammed. Hajj is that all Muslims go to Mecca during their lifetime. After Ramadan, Muslims congratulate each other by saying Kullu am wa antum bi-khair. This means “May you be blessed throughout the year.”
Another reason Ramadan special is it is mandated in the Quran.
“The month of Ramadan in which was revealed the Quran, a guidance for mankind and clear proofs for the guidance and the criterion (between right and wrong). So whoever of you sights (the crescent on the first night of) the month (of Ramadan), he must fast that month, and whoever is ill or on a journey, the same number (of days which one did not fast must be made up) from other days
Ramadan is the most sacred month of the year for Muslims — the Prophet Mohammed said “When the month of Ramadan starts, the gates of heaven are opened and the gates of Hell are closed and the devils are chained.”
Muslims believe it was during this month that God revealed the first verses of the Quran, Islam’s sacred text, to Mohammed, on a night known as “The Night of Power” (or Laylat al-Qadr in Arabic).