TYPES OF SALAT
a) Fard or obligatory Salat: Every believer is ordered by Allah to offer five obligatory prayers in a day. Failure to observe any one of the five obligatory prayers is a serious and punishable sin.
b) Nafl prayer This is a voluntary prayer which the Prophet (pbuh) observed before or after Fard at special and isolated occasions. It also includes those which he encouraged Muslims to pray. The Nafl prayer can be divided into three categories:
(i) Sunnat Muakkadah (compulsory). That is those which are emphasized by the holy Prophet (pbuh) and offered regularly by him before or after the Fard prayer but not praying this type of Salah doesnot invalidate (Fard)Obligatory Prayer
(ii) sunnat Ghair Muakkadah (optional). That is those offered only occasionally by Prophet Muhammad (pbuh).
(iii) Nafl Prayer (extra). This is an extra prayer. There is a reward for praying it an no sin for leaving it. It can be offered at any isolated instance according to the time and capacity of the believer. Prophet Muhammad (pbuh) encouraged the believers to pray Nafl to help make up for any minor omissions or other defects in the obligatory prayer.
NUMBER OF RAKAT FOR THE FIVE OBLIGATORY PRAYERS
(i) Fajr prayer: 2 Rakaat Sunnat Muakkadah, 2 Rakaat Fard
(ii) Dhuhr prayer: 2 or 4 Rakaat Sunnat Muakkadah , 4 Rakaat Fard, 2 Rakaat Sunnat Muakkadah and an unspecified number of Nafl as time and capacity allows.
Ibn Umar said "I prayed alone with Allah's Messenger (pbuh) 2 Rakaat before and 2 Rakaat after the Dhuhr prayer. (Bukhari and Muslim)
It is a familiar practice to offer 4 Rakaat Sunnat before Thuhr prayer, but this Hadith proves that 2 Rakaat Sunnat before the Thuhr prayer is also allowed.
(iii) Asr Prayer: 2 or 4 Rakaat Sunnat Ghair Muakkaadah , 4 Rakaat Fard.
Ali said, "Allah's Messenger (pbuh) used to pray 4 Rakaat before Asr prayer separating them with a salutation..." (Tirmidhi)
Another Hadith narrated by Ali says, Allah's Messenger (pbuh) used to pray two Rakaat before Asr prayer. (Abu Dawud)
(iv) Maghrib prayer.: 2 Rakat Nafl, 3 Rakat Fard, 2 Rakat Sunnat Muakadah and an unspecified number of Nafl as time and capacity allows.
Abdullah bin Mughaffal reported the Prophet ((pbuh) as saying, "Pray before the Maghrib prayer", adding when saying it the third time,
That was because he did not wish people to treat it as a compulsory Sunnat.
2 Rakaat Nafl after sunset and before the Maghrib prayer are allowed for those who wish to do so. For this the above Hadith is a sure proof. However, some people forbid this and others find it very strange if they see a person offer 2 Rakaat Nafl before Maghrib.
(v) Isha prayer: An unspecified number of Nafl Rakaat according to the time and capacity, 4 Rakaat Fard, 2 Rakaat Sunnat Muakkadah, unspecified number of Nafl as time and capacity allows and 3 Witr.
Some people insist very emphatically upon the offering of 4 Rakaat optional Sunnat before the Isha prayer but during our entire research we could not find a single proof, any practice or order from Prophet Muhammad (pbuh) or his companions to justify this claim. Certainly, it is allowed to pray Nafl while waiting for Jamaat.
Some people offer 2 Rakat Nafl after the Witr Prayer. However, there is an authentic Hadith which states that the Witr prayer should be offered after all the Nafl, which a person wishes to pray, have been offered. Ibn Umar reported that Allah's Messenger (pbuh) said "Make Witr as the last prayer of your night prayer." (mishkat)