All about Islam, the Muslim faith

Islam is the religion of around two billion women and men across the world. It rests on a simple yet demanding idea: there is only one God, Allah, who alone deserves to be worshipped, and Muhammad ﷺ is His Messenger. This page brings together the essentials for understanding Islam — the meaning of the word, what Muslims believe, the acts of worship, the sources of the religion, its history and its holy places — and points you to the detailed articles in this section.

What does the word “Islam” mean?

In Arabic, islam means submission: freely surrendering oneself to God. The word comes from the root s-l-m, which also conveys wholeness, safety and peace (salam). A Muslim (muslim) is therefore “one who submits to God”. The Quran presents this submission as the religion God accepts:

“Indeed, the religion in the sight of Allah is Islam.” (Quran 3:19)

For Muslims, Islam is not a religion that appeared in the seventh century: it is the very message conveyed by all the prophets, from Noah (Nuh) to Abraham (Ibrahim), Moses (Musa) and Jesus (Isa). Muhammad ﷺ is its final messenger, “the seal of the prophets” (Quran 33:40). This is why Islam is often grouped with Judaism and Christianity among the so-called Abrahamic religions, with which it shares many figures. We return to these points, and to a few common misconceptions, in our article The truth about Islam.

Islam is not only a creed: it covers worship, ethics and rules touching on personal, family and social life. The word sharia, often misunderstood, refers first of all to this “path” laid down by God across all these areas.

Muslims around the world

According to the Pew Research Center (report published in 2025), there were about 2 billion Muslims in 2020, or 25.6% of the world’s population. Islam is the world’s second-largest religion after Christianity (2.3 billion followers) and the one that grew the most between 2010 and 2020 (+347 million). The same report attributes this growth mainly to the young age and higher fertility of Muslim populations; religious switching, in either direction, has only a limited effect at the global level.

Contrary to a widespread belief, most Muslims are not Arabs: nearly six in ten live in Asia. Indonesia has the largest Muslim population (about 239 million in 2020), followed by Pakistan, India and Bangladesh. The Middle East and North Africa account for about a fifth, sub-Saharan Africa slightly less, and Europe about 45 million.

The great majority of Muslims are Sunni; Shia Muslims make up an estimated 10 to 13% of the total, according to the Pew Research Center (2009). They form the majority in Iran, Iraq, Azerbaijan and Bahrain, and large communities in Pakistan, India, Lebanon and Yemen.

The six pillars of faith

One day the angel Gabriel (Jibril) came, in the form of a man, and questioned the Prophet ﷺ in front of his companions. Asked “What is faith (iman)?”, he replied: “That you believe in Allah, His angels, His Books, His Messengers and the Last Day, and that you believe in the divine decree, its good and its evil” (Sahih Muslim 8). This hadith, known as the “hadith of Gabriel”, sums up the six articles of Muslim faith:

1. Belief in God: Allah is One, without partner or equal, the Creator of all things. The Quran describes Him through many names and attributes. See our article on God (Allah) in Islam and the list of the 99 names of Allah.
2. Belief in the angels: beings created from light who obey God; Gabriel conveyed revelation to the prophets.
3. Belief in the revealed Books: the Torah (Tawrat) given to Moses, the Psalms (Zabur) to David, the Gospel (Injil) to Jesus, and the Quran, revealed to Muhammad ﷺ.
4. Belief in the prophets and messengers: God sent messengers to every people; twenty-five are named in the Quran. Discover the life of Prophet Muhammad ﷺ.
5. Belief in the Last Day: resurrection, judgement, Paradise and Hell. See the Day of Judgement.
6. Belief in the divine decree (al-qadar): nothing happens in the universe without God knowing and permitting it, which takes nothing away from human responsibility.

The five pillars of Islam

The Prophet ﷺ said: “Islam is built upon five: testifying that there is no deity but Allah and that Muhammad is the Messenger of Allah, establishing prayer, giving zakat, performing Hajj and fasting in Ramadan” (Sahih al-Bukhari 8; Sahih Muslim 16). These are the fundamental acts of worship of a Muslim:

These pillars are exactly what is taught first to someone who embraces Islam: if you are considering it, read our guide How to convert to Islam.

Ihsan: the practice of the heart

In the same hadith, Gabriel finally asked the Prophet ﷺ about excellence (ihsan): “That you worship Allah as though you see Him; for though you do not see Him, He sees you.” Religion thus has three levels: outward acts (islam), convictions (faith) and inner excellence (ihsan).

Scholars accordingly distinguish the practice of the body — the movements, conditions and rules of prayer, ablution or fasting, which fiqh (Islamic jurisprudence) describes in detail — from the practice of the heart: sincerity, humility and inner focus (khushu’), love and reverent fear of God. One cannot go without the other. “Actions are judged only by intentions,” said the Prophet ﷺ (Sahih al-Bukhari 1; Sahih Muslim 1907). He also said: “In the body there is a piece of flesh: if it is sound, the whole body is sound, and if it is corrupt, the whole body is corrupt. Truly, it is the heart” (Sahih al-Bukhari 52; Sahih Muslim 1599). The movements of prayer can be learnt in a few weeks; the quality of the heart can keep growing for a lifetime.

Both dimensions require learning: you cannot perform ablution or prayer properly without knowing their rules. Imam al-Bukhari even titled a chapter of his collection “Knowledge comes before speech and action”, and the Prophet ﷺ said: “When Allah wishes good for someone, He gives him understanding of the religion” (Sahih al-Bukhari 71; Sahih Muslim 1037). Books are not always enough: it is invaluable to learn from a qualified, recognised teacher who will guide you step by step.

The sources of Islam: the Quran and the Sunnah

The Quran

For Muslims, the Quran is the Word of God, conveyed to Prophet Muhammad ﷺ by the angel Gabriel. Revelation began on a night in the month of Ramadan, around the year 610, and continued in stages for about twenty-three years, until the Prophet’s death ﷺ in 632. The text has 114 surahs and 6,236 verses according to the most widely used count. The Quran describes itself as a guide:

“Indeed, this Quran guides to that which is most suitable and gives good tidings to the believers who do righteous deeds that they will have a great reward.” (Quran 17:9)

It also states that “falsehood cannot approach it from before it or from behind it” (Quran 41:42). Learning the Quran and passing it on is among the best of deeds: “The best of you are those who learn the Quran and teach it” (Sahih al-Bukhari 5027). In another hadith, graded good (hasan) by several specialists, the Prophet ﷺ calls the people of the Quran “the people of Allah and those closest to Him” (Sunan Ibn Majah 215). To go further, read how to read and recite the Quran, or listen to the Quran recited by more than sixty reciters on our site.

The Sunnah

The Sunnah gathers the sayings, actions and approvals of the Prophet ﷺ. It explains and complements the Quran: it is through the Sunnah, for example, that we know the number of prayers and how to perform them. It has reached us through the hadiths, collected and scrutinised by scholars in major compilations such as those of al-Bukhari and Muslim. Find a selection of authentic sayings of the Prophet ﷺ.

From these two sources, jurists developed Islamic law, also drawing on the consensus of scholars (ijma’) and analogical reasoning (qiyas). Among Sunnis, four schools of law are recognised: Hanafi, Maliki, Shafi’i and Hanbali. They agree on the essentials and differ on some details, which is regarded as a legitimate flexibility.

A brief history of Islam

Islam was born in the seventh century in the Hijaz, the western region of the Arabian Peninsula, home to Makkah and Madinah. Around 610, Muhammad ﷺ received the first revelation in the cave of Hira, near Makkah. Persecuted, he and his companions emigrated to Madinah in 622: this is the Hijrah, the starting point of the Hijri calendar. In 630 the Prophet ﷺ returned to Makkah, which embraced Islam. By his death in 632, most of Arabia had accepted the new faith.

His first four successors, the caliphs Abu Bakr, Umar, Uthman and Ali (632–661), called “rightly guided” by Sunnis, unified Arabia and extended Muslim rule to Syria, Iraq and Egypt — provinces taken from the Byzantine Empire — and then to the Sasanian Persian Empire. The question of who should succeed the Prophet ﷺ divided the community: for the partisans of Ali (shi’at Ali, the origin of the word “Shia”), leadership should have remained in the Prophet’s family. The civil war of 656–661, and then the killing of his grandson al-Husayn at Karbala in 680, gradually deepened the separation between Sunnis and Shias.

The Umayyad dynasty (661–750), based in Damascus, extended the empire to Spain (from 711), Central Asia and the Indus valley. Under the caliph Abd al-Malik (685–705), Arabic became the language of administration and the first truly Islamic coins were struck. In 750 the Abbasids took power and founded Baghdad in 762, which became a great centre of science and letters. Political unity later fragmented, but Islam kept spreading, often through trade and the teaching of scholars, to West and East Africa, India and South-East Asia.

The holy places of Islam

Makkah and the Kaaba

Makkah (Mecca), in present-day Saudi Arabia, is home to the Sacred Mosque (al-Masjid al-Haram) and, at its centre, the Kaaba, towards which all Muslims turn in prayer. The Quran calls it “the first House [of worship] established for mankind” (Quran 3:96) and relates that Abraham and his son Ishmael raised its foundations (Quran 2:127). Before Islam, the Kaaba was surrounded by idols — 360 of them according to a hadith (Sahih al-Bukhari 4287) — among them Hubal, the chief deity of the Quraysh. The Prophet ﷺ had them destroyed when he returned to Makkah in 630, restoring the sanctuary to the worship of the One God. This is where the annual pilgrimage takes place: about 1.7 million pilgrims performed the Hajj in 1447 AH (2026), according to the Saudi General Authority for Statistics.

Madinah

Madinah is the city to which the Prophet ﷺ emigrated in 622, where he founded the first Muslim community and where he is buried, in his mosque (al-Masjid an-Nabawi). It is the second holiest city in Islam.

Jerusalem

Jerusalem (al-Quds) is home to al-Aqsa Mosque, the third holiest site in Islam. After the Hijrah, Muslims prayed facing Jerusalem for sixteen or seventeen months, before the qiblah was set towards the Kaaba (Sahih al-Bukhari 40). It was also to “al-Masjid al-Aqsa” that the Prophet ﷺ was taken during the Night Journey (Quran 17:1).

The Prophet ﷺ said: “Do not set out on a journey [for worship] except to three mosques: al-Masjid al-Haram, this mosque of mine and al-Masjid al-Aqsa” (Sahih al-Bukhari 1189; Sahih Muslim 1397). The obligatory pilgrimage, however, is made only to Makkah; visiting Madinah and Jerusalem is a meritorious act, but not a rite of Hajj.

Further reading

• The blessings of Islam: what faith brings to the individual and to society, in this world and the next.
• The truth about Islam: seven common misconceptions examined in the light of the texts and the facts.
• Converting to Islam: the steps and the first days of a new Muslim.
• The shahada: the meaning and conditions of the testimony of faith.
• Women in Islam: their status, rights and duties according to the Quran and the Sunnah.