Salafist reform movements take their name from the Arabic word salaf meaning "predecessor." The term is very broadly inclusive. Many movements, from moderate reformers to extremists, have called themselves salafists. The common denominator is the claim that the beliefs and customs they follow imitate exactly those of the Prophet Muhammad, his companions ("as-sahaba"), and the first generation of his followers.
Proponents of reform and revival who allowed some accommodation with the West and were considered salafists included Jamal al-Din al-Afghani and Muhammad Abduh, founders of a modern, progressive salafist movement. Radical salafists included Abdullah Azzam, Osama bin Laden, Sulayman al-Alwan, Abu Musab al-Suri, Abu Muhammad al-Maqdisi, and Abu Bakr Naji (a pseudonym), as well as the 1990s group, the Algerian GSPC.