As for the Shi'a, they are also known by several other names, including ar-Rafida [the Deserters or Rebels], al-Ghaliya [the Extremists] and at-Tayyara [the Flighty or Volatile Ones]. They came to be called the Shi'a [the Partisans] for the simple reason that they rallied to support [shayya'at] the cause of 'Ali (may Allah be well pleased with him), and considered him superior to all the rest of the Companions [of the Prophet (Allah bless him and give him peace)].
The Rafida were so called because of their rejection [rafd] of the majority of the Companions, and their refusal to accept the Imamate of Abu Bakr and 'Umar (may Allah be well pleased with them both). According to some, however, they were called ar-Rawafid [the Deserters] because they deserted Zaid ibn 'Ali, when he accepted the authority of Abu Bakr and 'Umar (may Allah be well pleased with them both) and declared himself in favor of their Imamate. Zaid said [of his former supporters]: "They have deserted me [rafaduni]," and so they came to be known as deserters [rafida].
There are also those who maintain that a Shi'i is someone who does not accept the precedence of 'Uthman over 'Ali (may Allah be well pleased with them both), whereas the Rawafid are those who [more actively] support the precedence of 'Ali over 'Uthman (may Allah be well pleased with them both).
Included among the Shi'a are the Qat'iyya [Positivists], who are so called because of their positive certainty [qat'] concerning the death of Musa ibn Ja'far.
Also included among them are the Ghaliya [Extremists], so called because of their excessively fanatical devotion [ghuluww] to 'Ali (may Allah be well pleased with him), and due to the fact that they improperly ascribed to him certain attributes of Lordship [rububiyya] and Prophethood [nubuwwa].
The names of the authors who compiled their textbooks are: Hisham ibn Hakam, 'Ali ibn Mansur, Abu'l-Ahwas, al-Husain ibn Sa'id, al-Fadl ibn Shadhan, Abu 'Isa al-Warraq, Ibn ar-Rawandi and al-Maniji. Their most numerous concentrations are to be found in the cities of Qum and Qashan [in Iran] and in the districts of Idris and Kufa [in 'Iraq].