Importance of Taraweeh

Another important feature of the month of Ramadhan is Tarawih. It is a special Salah (prayer) consisting of 20 rak'at which is performed immediately after the 'Isha' prayer. This Salah is Sunnah mu'akkaddah (repeatedly emphasized), and should not be missed. The Holy Prophet (Sallallahu Alaihi Wassallam) said, "Allah has made fasting in Ramadhan obligatory, and I have made the special prayer of Ramadhan (i.e. the Tarawih) a Sunnah". It is a Sunnah Mu'akkadah' 'alal-kifayah to perform Tarawih in jama'ah. It means that it is a Sunnah mu’akkaddah for the people of every mosque to arrange for the jama'at of the Tarawih. If a person after being sure that the jama'ah of Tarawih is being held in his mosque, performs the Tarawih in his home without jama'ah, the sunnah of the Tarawih is discharged, but he will be deprived of the great thawab (reward) of praying with jama'ah. So, one should perform the Tarawih in the mosque as far as possible. It is also a Sunnah to complete the recitation of the whole Quran in Tarawih in Ramadhan. It is thus advisable to request a hafiz (one who has memorized the Holy Quran by heart) to lead the prayer of Tarawih. However, paying any fee to the hafiz for this purpose is not allowed. If no such hafiz is available, the Tarawih should be led by any Imam, and he can recite in it whatever Surahs of the Holy Qur'an he remembers.

As a general practice, the Holy Qur'an is completed in most of the mosques a few days before the end of Ramadhan, on the 27th night or even earlier. In such a case, Tarawih should be continued till the last night of Ramadhan with recitation of different surahs. Those who leave Tarawih after the completion of the Holy Qur'an are not correct, because Sunnah of the Tarawih remains unchanged unto the last night.

The time of Tarawih begins after the performance of the obligatory (Fard) prayer of 'Isha. Therefore, the one who has not performed the Fard prayer of 'Isha cannot join the prayer of Tarawih. He should perform the Fard of 'Isha first, then join the Tarawih. If he missed some rak'at of Tarawih, he can complete it after the witr. For example, a person came to the mosque when the Imam has performed four rak'at of Tarawih. He should perform the Fard of 'Isha first, then join the jama'ah for Tarawih. If he has missed 4 or 6 rak'at of Tarawih, he should also perform the witr prayer with the Imam, then pray the four or six rak'at he has missed on his own, individually.
Courtesy: www.everymuslim.net