Muslims are people who follow or practice Islam, a monotheistic Abrahamic religion. Muslims consider the Quran, their holy book, to be the verbatim word of God as revealed to the Islamic prophet and messenger Muhammad. The majority of Muslims also follow the teachings and practices of Muhammad (sunnah) as recorded in traditional accounts (hadith).[29] The derivation of "Muslim" is from an Arabic word meaning "submitter" (to God).[30]

The beliefs of Muslims include: that God (Arabic: اللهAllāh) is eternal, transcendent and absolutely one (tawhid); that God is incomparable, self-sustaining and neither begets nor was begotten; that Islam is the complete and universal version of a primordial faith that has been revealed before through many prophets including Abraham, Ishmael, Isaac, Moses, and Jesus;[31] that these previous messages and revelations have been partially changed or corrupted over time (tahrif)[32] and that the Quran is the final unaltered revelation from God (Final Testament).[33]

As of 2015, 1.8 billion or about 24.1% of the world population are Muslims.[34] By the percentage of the total population in a region considering themselves Muslim, 91% in the Middle East-North Africa (MENA),[35] 81% in Central Asia,[36][37] 65% in the Caucasus,[38][39][40][41][42][43][44] 40% in Southeast Asia,[45][46] 31% in South Asia,[47][48] 30% in Sub-Saharan Africa,[49] 25% in AsiaOceania,[50] around 6% in Europe,[51] and 1% in the Americas.[52][53][54][55]

Most Muslims are of one of two denominations; Sunni (75–90%)[56] and Shia.[18] About 13% of Muslims live in Indonesia, the largest Muslim-majority country;[57] 31% of Muslims live in South Asia,[58] the largest population of Muslims in the world;[59] 20% in the Middle East–North Africa,[60] where it is the dominant religion;[61] and 15% in Sub-Saharan Africa.[62] Muslims are the overwhelming majority in Central Asia,[63] the majority in the Caucasus[64][65] and widespread in Southeast Asia.[66] India is the country with the largest Muslim population outside Muslim-majority countries.[67] Sizeable Muslim communities are also found in the Americas, China, Europe, and North Asia.[68][69][70] Islam is the fastest-growing major religion in the world.[71][72][73]

The religious practices of Muslims are enumerated in the Five Pillars of Islam: the declaration of faith (shahadah), daily prayers (salat), fasting during the month of Ramadan (sawm), almsgiving (zakat), and the pilgrimage to Mecca (hajj) at least once in a lifetime.[74][75]

To become a Muslim and to convert to Islam, it is essential to utter the Shahada, one of the Five Pillars of Islam, a declaration of faith and trust that professes that there is only one God (Allah) and that Muhammad is God's messenger.[76] It is a set statement normally recited in Arabic: lā ʾilāha ʾillā-llāhu muḥammadun rasūlu-llāh (لَا إِلٰهَ إِلَّا الله مُحَمَّدٌ رَسُولُ الله) "There is no god but Allah, (and) Muhammad is the messenger of God."[77]

In Sunni Islam, the shahada has two parts: la ilaha illa'llah (there is no god but God), and Muhammadun rasul Allah (Muhammad is the messenger of God),[78] which are sometimes referred to as the first shahada and the second shahada.[79] The first statement of the shahada is also known as the tahlīl.[80]

In Shia Islam, the shahada also has a third part, a phrase concerning Ali, the first Shia Imam and the fourth Rashid caliph of Sunni Islam: وعليٌ وليُّ الله (wa ʿalīyyun walīyyu-llāh), which translates to "Ali is the wali of God".[81]

The word muslim (Arabic: مسلم‎, IPA: [ˈmʊslɪm]; , , or moslem , [82]) is the active participle of the same verb of which islām is a verbal noun, based on the triliteral S-L-M "to be whole, intact".[83][84] A female adherent is a muslima (Arabic: مسلمة‎) (also transliterated as "Muslimah"[85] ). The plural form in Arabic is muslimūn (مسلمون) or muslimīn (مسلمين), and its feminine equivalent is muslimāt (مسلمات).

The ordinary word in English is "Muslim". The word Mosalman (Persian: مسلمان‎, alternatively Mussalman) is a common equivalent for Muslim used in Central and South Asia. In English it was sometimes spelled Mussulman and has become archaic in usage. Until at least the mid-1960s, many English-language writers used the term Mohammedans or Mahometans.[86] Although such terms were not necessarily intended to be pejorative, Muslims argue that the terms are offensive because they allegedly imply that Muslims worship Muhammad rather than God.[87] Other obsolete terms include Muslimite[88] and Muslimist.[89]

A Muslim is a person who has dedicated his worship exclusively to God...Islam means making one's religion and faith God's alone.[90]

The Qur'an describes many prophets and messengers within Judaism and Christianity, and their respective followers, as Muslim: Adam, Noah, Abraham, Ishmael, Jacob, Moses, and Jesus and his apostles are all considered to be Muslims in the Qur'an. The Qur'an states that these men were Muslims because they submitted to God, preached His message and upheld His values, which included praying, charity, fasting and pilgrimage. Thus, in Surah 3:52 of the Qur'an, Jesus' disciples tell him, "We believe in God; and you be our witness that we are Muslims (wa-shahad be anna muslimūn)." In Muslim belief, before the Qur'an, God had given the Tawrat (Torah) to Moses, the Zabur (Psalms) to David and the Injil (Gospel) to Jesus, who are all considered important Muslim prophets.

World Muslim population by percentage (2010 data from Pew Research Center)
A map of Muslim populations by absolute number, (Pew Research Center, 2009)

The most populous Muslim-majority country is Indonesia, home to 12.7% of the world's Muslims,[91] followed by Pakistan (11.0%), Bangladesh (9.2%), and Egypt (4.9%).[92] About 20% of the world's Muslims live in the Middle East and North Africa.[91][93]

Sizable minorities are also found in India, China, Ethiopia, the Americas, Australia and parts of Europe. The country with the highest proportion of self-described Muslims as a proportion of its total population is Morocco.[2] Converts and immigrant communities are found in almost every part of the world.

Over 75–90% of Muslims are Sunni.[16][17] The second and third largest sects, Shia and Ahmadiyya, make up 10–20%,[18][94] and 1%[20] respectively.

With about 1.9 billion followers (2019), almost a quarter of earth's population,[95] Islam is the second-largest and the fastest-growing religion in the world.[96] due primarily to the young age and high fertility rate of Muslims,[97] with Muslim having a rate of (3.1) compared to the world average of (2.5). According to the same study, religious switching has no impact on Muslim population, since the number of people who embrace Islam and those who leave Islam are roughly equal.[97]

A Pew Center study in 2016 found that Muslims have the highest number of adherents under the age of 15 (or 34% of the total Muslim population) of any major religion, while only 7% are aged 60+ (the smallest percentage of any major religion). According to the same study, Muslims have the highest fertility rates (3.1) of any major religious group.[98] The study also found that Muslims (tied with Hindus) have the lowest average levels of education with an average of 5.6 years of schooling, though both groups have made the largest gains in educational attainment in recent decades among major religions.[98] About 36% of all Muslims have no formal schooling,[98] and Muslims have the lowest average levels of higher education of any major religious group, with only 8% having graduate and post-graduate degrees.[98]

Muslim culture or Islamic culture are terms used to describe the cultural practices common to Muslims and historically Islamic people. The early forms of Muslim culture, from the Rashidun Caliphate to early Umayyad period, were predominantly Arab, Byzantine, Persian and Levantine. With the rapid expansion of the Islamic empires, Muslim culture has influenced and assimilated much from the Persian, Egyptian, Caucasian, Turkic, Mongol, South Asian, Malay, Somali, Berber, Indonesian, and Moro cultures.