Hindu texts Vedas: the Rigveda, the Yajurveda, the Samaveda and the Atharvaveda. Each Veda has been subclassified into four major text types – the Samhitas (mantras and benedictions), the Aranyakas (text on rituals, ceremonies, sacrifices and symbolic-sacrifices), the Brahmanas (commentaries on rituals, ceremonies and sacrifices), and the Upanishads (text discussing meditation, philosophy and spiritual knowledge). The Upanishads are a collection of Hindu texts which contain some of the central philosophical concepts of Hinduism. The Upanishads are commonly referred to as "Vedānta", variously interpreted to mean either the "last chapters, parts of the Veda" or "the object, the highest purpose of the Veda".
Vedas Brahmanas (commentaries on rituals, ceremonies and sacrifices), and the Upanishads (texts discussing meditation, philosophy and spiritual knowledge). Some scholars add a fifth category – the Upasanas (worship). The various Indian philosophies and denominations have taken differing positions on the Vedas. Schools of Indian philosophy which cite the Vedas as their scriptural authority are classified as "orthodox" (āstika). Other śramaṇa traditions, such as Lokayata, Carvaka, Ajivika, Buddhism and Jainism, which did not regard the Vedas as authorities, are referred to as "heterodox" or "non-orthodox" (nāstika) schools. Despite their differences, just like the texts of the śramaṇa traditions, the layers of texts