Ramadan
Ramadan is the ninth month in the Islamic calendar and Muslims are required to fast during this month. The fast is to abstain from food, drink and marital relations from dawn until sunset, but Muslims are also encouraged to increase in their worship in general and also the recital of the Holy Qur’an. In accordance with the practice of Prophet Muhammad (peace be upon him). It is unlawful (haram) to fast the two days of Eid-ul-Fitr and Eid-ul-Adha, and the three days after Eid-ul-Adha, known as the days of Tashriq.
Supplications
When beginning the fast – Suhur (sehri):
وَبِصَوْمِ غَدٍ نَّوَيْتُ مِنْ شَهْرِ رَمَضَانَ
Translation: I intend to keep the fast for tomorrow in the month of Ramadan
[Abu Dawud]
Transliteration: Wa bi-sawmi ghadin nawaytu min shahri ramadan
When breaking the fast – Iftar
اللَّهُمَّ اِنِّى لَكَ صُمْتُ وَبِكَ امنْتُ (وَعَليْكَ تَوَكّلتُ) وَ عَلىرِزْقِكَ اَفْطَرْتُ
Translation: O Allah! I fasted for You and I believe in You [and I put my trust in You] and
I break my fast with Your sustenance.
[Abu Dawud]
Transliteration:
Allahumma Inni laka sumtu wa bika amantu [wa alayka tawakkalto] wa ‘ala rizqika aftartu
Wa bi-sawmi ghadin nawaytu min shahri ramadan
["wa ‘alayka tawakkaltu" is quoted in some books of knowledge - but not all, hence it is in brackets]

Fasting
"O ye who believe! Fasting is prescribed to you as it
was prescribed to those before you, that ye may (learn) self-restraint"