Their chosen path was one of distancing themselves from 'Uthmaan ibn 'Affaan and 'Alee ibn Abee Taalib (radhi-yallaahu 'anhumaa), and condoning walking out against the Imaam (leader) and seeking to overthrow him if he opposes the Sunnah. Likewise, they would make takfeer (render someone a kaafir) of anyone who commits a major sin and claim that he will forever abide in the Fire of Hell.

Ash-Shahrastaanee defines them as: ((Anyone who walks out against (seeking to overthrow) the true appointed Imaam (leader) upon whose leadership the Jamaa'ah is in agreement is called a Khaarijee. This is the case, despite whether the walking out (against the Imaam) occurred in the days of the Rightly-Guided Khulafaa. or other than them from the Taabi'een)).

And some of the pious predecessors used to call all those who practiced Islaam based upon their desires as Khawaarij.

The Khawaarij were the first sect to appear in the history of Islaam, splitting up into more than 20 different sub-sects. However, it is said that the major sub-sects of the Khawaarij are seven:

1) al-Mahkamah al-Oolaa;
2) al-Azaariqah;
3) an-Najdaat;
4) ath-Thu'aalabah;
5) al-'Ajaaridah;
6) al-Abaadhiyyah;
7) as-Safriyyah.

Some of the other sub-sects include:

1) al-Ibaathiyyah;
2) ash-Shamraakhiyyah;
3) as-Salaydiyyah;
4) as-Sirriyyah;
5) al-'Azriyyah;
6) al-'Ajradiyyah;
7) ash-Shakkiyyah;
8) al-Fadhaliyyah;
9) al-Bayhasiyyah;
10) al-'Atwiyyah;
11) al-Fadeekiyyah;
12) al-Ja'diyyah;
13) ash-Shaybiyyah;
14) al-Hurooriyyah;
15) al-Khamariyyah;
16) ash-Sharaah.