Ramadan is the ninth month of the Islamic calendar, which is based on the lunar cycle. Every adult Muslim who has no legitimate excuse should fast from dawn till sunset. Ramadan is not simply to deprive believers through hunger and thirst, but to work on the cleansing of the heart and spirit. As prophet Mohammad (Peace Be Upon Him) explained, fasting also means to watch your tongue, thoughts, talk, interaction and so on.
It was the practice of Prophet Mohammad (Peace Be Upon Him) to gather his companions before the start of Ramadan and admonish them about this blessed month. In one such occasion he (Peace Be Upon Him) said, "People, a great blessed month has come upon you, which contains Night of power, which in its virtues is better than a thousand months. God has made fasting during it an obligation, and steadfastly observing its nights in worship a voluntary act. ... It is the month of patience, and the reward for patience is Paradise. It is the month of goodwill, during which provisions are multiplied. Whoever feeds a fasting person will be compensated with forgiveness of sins and salvation of his soul from Hell. He will also receive a reward equal to that of the person he feeds, without causing him any reduction."
Ramadan, which began Aug. 1 this year, is the month of devotion and reflection. Muslims fast during the entire day and spend the major portion of the night praying and reciting Quran. It's a refresher course for the empowerment of the heart and soul so believers apply this training for the rest of the year.
Ramadan brings a person closer to God. God mentions in Quran that He is near and close to His servants, and when they call to their Lord He listens and answers their call.