The caliph (or Khalifa in Arabic) is the state ruler and leader. The caliph should rule per the Islam guides and teachings. The imam is religious leader in the mosque and in any other worship gathering. The imam should, also, rule per the Islam guides and teachings. So far, both are following Islam guides and teachings, how there will be conflicts or problems. If the Caliph deviates, intentionally or by mistake, the imams can remind him and they will find good response from him since both the Caliph and the Imams are looking for the same objective; that is submission to God (Islam is an Arabic word that means Submission to God).
The Caliphs including the Rashidun, the Umayyads, and the Abbassids.
shi'a
A Caliph or khalifa is a sort of religious dictator, an Islamic ruler, considered to be the political-religious leader of an Islamic community of believers, ruling in accordance with Islamic law.
There is no singular person who represents the entire worldwide Islamic community like the Pope represents all Catholics. In Shiite Islam, there are the Great Ayatollahs which represent vast swathes of the Shiite community. Smaller Islamic communities are represented by Mullahs and Imams for each congregation.
as u know that there were four caliphs after hazrat Muhammad ( P B U H )wen there is no leader the unity is broken so after longfights the first caliph hazrat abu bakar sidduiqe razitallah anah was made r first caliph or in other words : The death of Muhammad in 632 created confusion in the nascent Muslim community, for Muhammad had left no details as to who should succeed him. After a heated discussion by the senior members of the community, Abu Bakr was selected as the first caliph.
Caliphs were successors of Muhammad as spiritual and temporary leader of the Muslims. They administered the empire by keeping everyone in line.
This group is called the Shi'a. Its members were known as Shiites.
It seems like the question is looking for the answer "Caliph". Caliphs used to be the "Pope of Sunni Islam". They were religious leaders and political leaders, although they were more often one than the other. (In the early period, the Rashidun Caliphs were both, the Umayyad and Abbassid Caliphs were more political than the religious, and the Seljuk and Ottoman Caliphs were more religious than political.) There has been no Caliph since the abolition of the Caliph in Istanbul by Mustafa Kemal Atatürk in 1936. There are numerous varieties of religious non-political Islamic leaders such as Imams (Islamic Priests), Qadis (Islamic Judges), Mullahs (Islamic "Bishops"), Faqihs (Islamic Jurists), 'Alems (Islamic Scholars), Ayatollahs (Shiite Islamic "Patriarchs"), and Muftis (Islamic "Archbishops"). While they may at times have political power, like the Ayatollahs of Iran, their primary function is not political. Most Islamic scholars believe that there should be a divorce between the actual rulers and the Islamic religious leadership so that Islam cannot be blunted and warped to defend immoral political practices. There are also numerous varieties of political non-religious Islamic leaders such as Sultans, Kings, Emirs, Presidents, Prime Ministers, Ministers, Governors, etc. While these individuals may have religious authority, this is not their primary function. An example of this religious function is that Sultan Suleiman I created an Ottoman Legal Code based on Qur'anic values which has been upheld by the Qadis and the Faqihs as a valid interpretation of Islamic Law.
They are called Shiites. refer to related question for more information.
The Shiites group. Refer to question below for morte information.
calipa
Muhammad SAW/PBUH is the leader of the islamic faith. When i say leader i mean the founder the person who founded Islam.