Sunnah salat

Sunnah prayer (Arabic: صلاة السنة‎‎) is an optional salah that can be performed by Muslims at almost any time of the day. These prayers are performed in addition to the five daily prayers, which are compulsory for all Muslims. There are a range of prayers available: some are done at the same time as the compulsory prayers, some are done only at certain times, e.g. late at night, and some are only done for specific occasions such as during a drought. All of these optional prayers were originally performed by Muhammad.

Group of Muslims performing Sunnah Salah after Jumua'ah Salaat at Orient Islamic School Hall in KZN Durban South Africa on Friday 2014.01.24

Tahajjud (Arabic: صلاة التهجد‎‎) prayer is performed at night time, and it is recommended that it Should be performed after first going to sleep for some part of the evening. Scholars have different opinions about whether sleeping first is absolutely required or not. In Saudi Arabia during the fasting month of Ramadan, there are many people who leave the Tarawih prayers in the main masjid in a hurry so that they can go home, go to sleep, and then wake up to perform their Tahajjud prayers in the early morning. Others simply stay in the mosque and perform these optional prayers before going home.

The time for the Tahajjud prayers falls between the prayer times of the isha'a prayers and the fajr prayers. It is also recommended that the prayers be done in the last third of the night. Muslims believe that the reward is greater for those who do this prayer at a later time. (It is harder to wake up and pray early in the morning, making the person's effort greater, resulting in a greater reward from God.)

Each prayer for a Muslim is made up with repeated actions: from standing, to bowing on the floor, to standing again is called one raka'ah. The Tahajjud prayer consists of a minimum of two raka'ah and the maximum number is unlimited.

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Wikipedia