A mosque (/mɒsk/; from Arabic: مَـسْـجِـد, translit. masjid) is a place of worship for Muslims. There are strict and detailed requirements in Sunni jurisprudence (Arabic: فِـقْـه, fiqh) for a place of worship to be considered a mosque, with places that do not meet these requirements regarded as musallas. There are stringent restrictions on the uses of the area formally demarcated as the mosque (which is often a small portion of the larger complex), and in the Islamic Sharī‘ah (Arabic: شَـرِيْـعَـة, Law), after an area is formally designated as a mosque, it remains so until the Last Day. Many mosques have elaborate domes, minarets, and prayer halls, in varying styles of architecture. Mosques originated on the Arabian Peninsula, but are now found in all inhabited continents. The mosque serves as a place where Muslims can come together for Ṣalāh (Arabic: صَـلَاة, meaning prayer) as well as a center for information, education, social welfare, and dispute settlement. The Imām (Arabic: إِمَـام, Leader) leads the congregation in prayer.
Arab-plan or hypostyle mosques are the earliest type of mosques, pioneered under the Umayyad Dynasty. These mosques have square or rectangular plans with an enclosed courtyard and covered prayer hall. Historically, in the warm Middle Eastern and Mediterranean climates, the courtyard served to accommodate the large number of worshippers during Friday prayers. Most early hypostyle mosques had flat roofs on prayer halls, which required the use of numerous columns and supports. One of the most notable hypostyle mosques is the Great Mosque of Cordoba in Spain, the building being supported by over 850 columns. Frequently, hypostyle mosques have outer arcades so that visitors can enjoy the shade. Arab-plan mosques were constructed mostly under the Umayyad and Abbasid dynasties; subsequently, however, the simplicity of the Arab plan limited the opportunities for further development, the mosques consequently losing popularity. The first departure within mosque design started in Persia (Iran). The Persians had inherited a rich architectural legacy from the earlier Persian dynasties, and they began incorporating elements from earlier Parthian and Sassanid designs into their mosques, influenced by buildings such as the Palace of Ardashir and the Sarvestan Palace. Thus, Islamic architecture witnessed the introduction of such structures as domes and large, arched entrances, referred to as iwans. During Seljuq rule, as Islamic mysticism was on the rise, the four-iwan arrangement took form. The four-iwan format, finalized by the Seljuqs, and later inherited by the Safavids, firmly established the courtyard façade of such mosques, with the towering gateways at every side, as more important than the actual buildings themselves. They typically took the form of a square-shaped central courtyard with large entrances at each side, giving the impression of gateways to the spiritual world. The Persians also introduced Persian gardens into mosque designs. Soon, a distinctly Persian style of mosques started appearing that would significantly influence the designs of later Timurid, and also Mughal, mosque designs. The Ottomans introduced central dome mosques in the 15th century. These mosques have a large dome centered over the prayer hall. In addition to having a large central dome, a common feature is smaller domes that exist off-center over the prayer hall or throughout the rest of the mosque, where prayer is not performed. This style was heavily influenced by Byzantine architecture with its use of large central domes. Hajja Soad's mosque took a pyramid shape that is a creative style in Islamic architecture. The Faisal Mosque in Islamabad, Pakistan, in a relatively unusual design fuses contemporary lines with the more traditional look of an Arab Bedouin's tent, with its large triangular prayer hall and four minarets. However, unlike traditional mosque design, it lacks a dome. The mosque's architecture is a departure from the long history of South Asian Islamic architecture. Mosques built in Southeast Asia often represent the Indonesian-Javanese style architecture, which are different from the ones found throughout the Greater Middle East. The ones found in Europe and North America appear to have various styles but most are built on Western architectural designs, some are former churches or other buildings that were used by non-Muslims. In Africa, most mosques are old but the new ones are built in imitation of those of the Middle East. This can be seen in the Abuja National Mosque in Nigeria and others.