The three divisions of Vedas are Samhita – Brahmana and
Aranyaka.
Samhita are inspired verses or mantras – They emanate from
the realm of pure consciousness. They are revealed by the divinity through the
medium of illumined souls. The aim of Samhita is universal wellbeing.
Brahmanas are commentaries in prose. They deal with the
rituals.
Aranyakas are forest treatises – they are spiritual and
speculative in nature.
Upanishads are part of Samhitas, Brahmanas and Aranyakas.
They contain fearless enquiry and intuitive observations.