(12 Rabi')
At this time Muslims think about Muhammad (pbuh), and the events of his life.
(27 Rajab)
The festival celebrates Prophet Muhammad's (pbuh) journey from Mecca to Jerusalem in a single night on a winged creature called Buraq. From Jerusalem he ascended into heaven, where he met the earlier prophets, and eventually God.
(15 Shabaan)
The Night of Forgiveness (Lailat-ul-Bara'h) takes place two weeks before Ramadan. Muslims spend the night in prayer seeking God's guidance and forgiveness for their sins. It is an opportunity to put the past behind them and forgive each other. Many Muslims believe that a person's destiny is fixed for the coming year by God on this night.
(27 Ramadan)
The Night of Power marks the night in which the Qur’an was first revealed to the Prophet Muhammad (pbuh) by Allah. No one knows of its exact date, but the Prophet (pbuh) said that it falls in the last 10 nights of Ramadan, and is most likely on the 27th night
[Lo! We revealed it on the Night of Power. Ah, what will convey unto thee what the Night of Power is! The Night of Power is better than a thousand months. The angels and the Spirit descend therein, by the permission of their Lord, with all decrees. (That night is) Peace until the rising of the dawn.] (Surat Al-Qadr 97:1 – 5)
(1 Shawwal)
This marks the end of Ramadan, the month of fasting, and is a festival of great celebration. In Islamic countries it is a public holiday.
(10 Dhul-Hijja)
This festival marks the end of the Hajj or holy pilgrimage, which is one of the 5 pillars of Islam. However it is celebrated by all Muslims, not just those who are on the pilgrimage.