According to a famous saying of the Prophet Islam consists of five pillars which are as follows: affirmation of the faith (shahadah), that is, witnessing that La ilaha illa'Llah (There is no divinity but Allah) and Muhammadun rasul Allah (Muhammad is the Messenger of Allah); the five daily prayers (al-salat) which Muslims perform facing Makkah; fasting (al-sawm) from dawn to sunset during the month of Ramadan; making the pilgrimage to Makkah (al-hajj) at least once in a lifetime if one's financial and physical conditions permit it; and paying a 2 1/2% tax (al-zakat) on one's capital which is used for the needs of the community. Muslims are also commanded to exhort others to perform good acts and to abstain from evil. Ethics lies at the heart of Islamic teachings and all men and women are expected to act ethically towards each other at all times. As the Prophet has said, "None of you is a believer until you love for your brother what you love for yourself."
As for faith according to Islam (al-iman), it means having faith in God, His angels, His books, His messengers, the Day of Judgment and God's determination of human destiny. It is important to understand that the definition of al-iman refers to books and prophets in the plural thus pointing directly to the universality of revelation and respect for other religions emphasized so much in the Quran. There is also the important concept, al-ihsan or virtue, which means to worship God as if one sees Him, knowing that even if one does not see Him, He sees us. It means to remember God at all times and marks the highest level of being a Muslim.