Hindu philosophy refers to a group of darśanas (philosophies, world views, teachings) that emerged in ancient India. The mainstream Hindu philosophy includes six systems (ṣaḍdarśana) – Samkhya, Yoga, Nyaya, Vaisheshika, Mimamsa and Vedanta. These are also called the Astika (orthodox) philosophical traditions and are those that accept the Vedas as authoritative, important source of knowledge.[note 1][note 2] Ancient and medieval India was also the source of philosophies that share philosophical concepts but rejected the Vedas, and these have been called nāstika (heterodox or non-orthodox) Indian philosophies. Nāstika Indian philosophies include Buddhism, Jainism, Cārvāka, Ājīvika, and others. 

Scholars have debated the relationship and differences within āstika philosophies and with nāstika philosophies, starting with the writings of Indologists and Orientalists of the 18th and 19th centuries, which were themselves derived from limited availability of Indian literature and medieval doxographies. The various sibling traditions included in Hindu philosophies are diverse, and they are united by shared history and concepts, same textual resources, similar ontological and soteriological focus, and cosmology. While Buddhism and Jainism are considered distinct philosophies and religions, some heterodox traditions such as Cārvāka are often considered as distinct schools within Hindu philosophy.
are they limited?
sibling traditions included in Hindu philosophies are diverse