Hindu philosophy or Vedic philosophy is the set of Indian philosophical systems developing alongside the religion of Hinduism and emerging in the Iron and Classical periods, which consists of six orthodox schools of thought (shad-darśana): Samkhya, Yoga, Nyaya, Vaisheshika, Mimamsa and Vedanta. In Indian tradition, the word used for philosophy is Darshana (viewpoint or perspective), from the Sanskrit root drish ('to see, to experience').
These are also called the āstika philosophical traditions: those that accept the Vedas as an authoritative, important source of knowledge. Indian philosophy during the ancient and medieval periods of India also yielded philosophies that share philosophical concepts with these āstika philosophies but rejected the Vedas, and these have been called nāstika (heterodox or non-orthodox) Indian philosophies, including Buddhism, Jainism, Chārvāka, Ājīvika, and others, which are thus classified under Indian but not Hindu philosophy.
Western 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 (nāstika) traditions such as Cārvāka are often considered as distinct schools within Hindu philosophy because the word Hindu is also an exonym and historically, the term has also been used as a geographical and cultural identifier for people living in the Indian subcontinent.