Ramadan or Ramadhan

 
Ramadan or Ramadhan (in Arabic: رمضان)
is the ninth month of the lunar Hijri (Islamic religious calendar systems). Throughout this month Moslems perform a series of religious activities including fasting, prayer tarawih, warning the decline of Al-Quran, seek Laylatul Qadr night, multiply reading the Quran and then end it by paying tithes and a series of Eid celebrations. Specificity of Ramadan for Moslems is reflected in the Quran in surah Al Baqarah verse 185 which means:
شَهْرُ رَمَضَانَ الَّذِي أُنْزِلَ فِيهِ الْقُرْآنُ هُدًى لِلنَّاسِ وَبَيِّنَاتٍ مِنَ الْهُدَى وَالْفُرْقَانِ فَمَنْ شَهِدَ مِنْكُمُ الشَّهْرَ فَلْيَصُمْهُ وَمَنْ كَانَ مَرِيضًا أَوْ عَلَى سَفَرٍ فَعِدَّةٌ مِنْ أَيَّامٍ أُخَرَ يُرِيدُ اللَّهُ بِكُمُ الْيُسْرَ وَلا يُرِيدُ بِكُمُ الْعُسْرَ وَلِتُكْمِلُوا الْعِدَّةَ وَلِتُكَبِّرُوا اللَّهَ عَلَى مَا هَدَاكُمْ وَلَعَلَّكُمْ تَشْكُرُونَ
     "Ramadan, the month in which inherited the Al-Quran as a guidance for mankind and explanations of instructions and a differentiator. Therefore, whoever among you is present in that month, then let him fast the month ..."

Fasting Ramadhan (Shaum (in Arabic صوم)

This means refraining from eating and drinking as well as any acts that could break the fast, from dawn hinggalah sunset, to increase the piety of a Muslim. Fasting command spoken by Allah in the Quran surah Al-Baqarah verse 183.
يَا أَيُّهَا الَّذِينَ آمَنُوا كُتِبَ عَلَيْكُمُ الصِّيَامُ كَمَا كُتِبَ عَلَى الَّذِينَ مِنْ قَبْلِكُمْ لَعَلَّكُمْ 
تَتَّقُونَ
"O you who believe, have been obliged to fast for you as required upon the peoples who were before you, may you be the ones who fear Him."

Salat Tarawih (sometimes called teraweh or Taraaweeh)
is a voluntary prayer performed only in the month of Ramadan special. Tarawih in Arabic is the form jama 'from ترويحة defined as "a moment to rest". The timing of this is the sunnah prayer after the evening ', usually performed in congregation at the mosque. Interesting facts about this prayer is that the Prophet sallallaahu 'alaihi wa sallam only ever do it in congregation in 3 occasions. Mentioned that the Prophet sallallaahu 'alaihi wa sallam then did not continue on subsequent nights for fear it would be required of the Muslim Ummah (see subsections hadith about tarawih).