LAYLATUL QADR (THE NIGHT OF TAQDEER AND AZMATH)
Qadr means fate or predestination of all events, of which except Allah (Glory be to Him) no one knows. And Laylatul Qadr means the Night of Power which is the crowning glory of the month of Ramadhan. It is associated with the sending down of the Qur’an, the last Book from Allah revealed on His last Prophet i.e., Prophet Muhammad (May Allah honor Him and grant Him peace), for the guidance of mankind. 
Muslim scholars believe that while the Qur’an was revealed over a period of 23 years, the Night of Power is considered the night in which the revelation of Qur’an and the prophethood of Prophet Muhammad(May Allah honor Him and grant Him peace) began.
The Qur’an describes this Night as follows:
"We have indeed revealed this (message) in the Night of Power. And what will explain to thee what the Night of Power is? The Night of Power is better than a thousand months. Therein come down the angels and the spirit by God's permission, on every errand: Peace! This until the rise of Morning."Qur’an.Surah Qadr 97:1-5.
“Ha. Mim. By the book that makes things clear. We sent it down during a blessed night. For We (ever) wish to warn (against evil). In that (night) is made distinct every affair of wisdom, by command, from Our Presence. For We (ever) send (revelations), as a mercy from Thy Lord: for He hears and knows (all things)” Qur’an.Surah Dukhan 44:1-6 
The Night of Poweris the night of spiritual bliss. The Prophet Muhammad (May Allah honor Him and grant Him peace) said about Lailatul-Qadr:
It is narrated by Abu Hurairah (R) that Prophet said, “Whoever stood for the prayers in the night of Qadr out of sincere Faith and hoping for a reward from Allah, then all his previous sins will be forgiven ." Sahih Al Bukhari Vol 3: 231.
Matters of future of all the human beings are given to the angels for the upcoming year. Allah says: “Therein descend the angels and the Ruh [Jibreel (Gabriel)] by Allah's Permission with all Decrees.” Qur’an.Surah Qadr 97:4
Qatadah and others (May Allah have Mercy on Them) have said, "The matters are determined during it, and the times of death and provisions are measured out (i.e., decided) during it.'' Tafseer Ibn Kathir
Further Allah says, “Therein is decreed every matter of decree.” Qur’an.Surah Dukhan 44:4
Therein (that night) is decreed every matter. It was narrated from Ibn Umar® that it means, on Laylatul-Qadr, the decrees (Taqdeer) are transferred from Al-Lawh Al-Mahfuz to the (angelic) scribes who write down the decrees of the (coming) year including life span, provision, and what will happen until the end of the year. Tafseer Ibn Kathir
Better than a thousand months
Allah (Glory be to Him) says in Qur’an.Surah Qadr 97:3 - “The Night of Power is better than a thousand months.” A thousand months are equivalent to 83 years and 4 months. Fortunate is the person who spends this night in prayer. The man or woman, who prays for the whole night during this Night, will deserve blessings and reward for the period as if he or she had been praying for eighty three years and four months consecutively. Since the Night of Power is better than one thousand months no one can actually measure the extent as to how much better it is.
Exclusive for the Ummah of Prophet Muhammad (May Allah honor Him and grant Him peace)
Ziyad related to me from Malik (R) that he had heard a man he trusted of the people of knowledge say, "The Messenger of Allah (May Allah bless him and grant Him Peace), was shown the life spans of the people (who had gone) before him, or what Allah willed of that, and it was as if the lives of the people of his community had become too short for them to be able to do as many good actions as others before them had been able to do with their long lives, so Allah gave him Laylat al-Qadr, which is better than a thousand months." Mutwatta Imam Malik I'tikaf in Ramadan Book 19.6.16, Fiqh-us-Sunnah Fiqh 3.144.
"Whoever stands (in prayer) during the Night of Al-Qadr with faith and expecting reward (from Allah), he will be forgiven for his previous sins." Fath Al-Bari 4:294, and Sahih Al Muslim Vol 1:253
Although there are different reports in different traditions regarding the exact night, it is almost unanimous that the blessed night occurs in one of the last ten nights of Ramadhaan and more probably in one of the last ten odd nights i.e. 2lst, 23rd, 25th 27th or 29th night.
The popular opinion is, however, in favour of the 27th Night of Ramadhaan but that is not absolutely certain. The traditions indicate that it is to be sought in one of the last ten nights and preferably in the last three odd nights. It was therefore the practice of The Prophet Muhammad (May Allah honor Him and grant Him peace) and his companions (May Allah be pleased with Him) to make Itikaaf in the Masjid for the whole time offering Divine service during the last ten days of Ramadhaan. Aisha (R) reported that the Apostle of Allah said: “Search for the Blessed Night in the odd (nights) from the last ten (nights) of Ramadhaan” Sahih Al Bukhari Vol 3: 234. 
Aisha (R) has narrated another saying: “I asked: O Messenger of Allah! Tell me if I were to find a Night of Power, what should I recite therein?” The Prophet Muhammad (May Allah honor Him and grant Him peace) advised her to recite: Allahumma innaka 'afu'wwun tuhibbul 'afwa fa'fu 'annee.O Allah! You are Forgiving, You love forgiveness, so forgive me.Al-Tirmidhi Hadith 2091 Musnad Ahmad Vol 6:182, An-Nasai Vol 6:218 and Ibn Majah Vol 2:1265 and Al-Hakim Vol 1:530.
Special attention should therefore be given to the excessive recitation of this dua on the blessed night. Furthermore one may engage in lengthy rakaats of Tahajjud salaat, Tilaawat (reading) of the Qur’an, Dua, Zikr, etc.