According to orthodox Hindu tradition, the Vedas are ) and are the paramount source of Brahmin traditions.
Shruti includes not only the four Vedas (the Rigveda, the Yajurveda, the Samaveda and the Atharvaveda), but also their respective Brahmanas, Aranyakas and Upanishads.
Brahman and Brahmin (brahman, brahmán, masculine) are not the same.
Brahman (bráhman, neuter), since the Upanishads, refers to the Supreme Self.
Brahmin or Brahmana (brahmán, brāhmaṇa) refers to an individual.
Additionally, the word Brahma (brahmā, masculine) refers to first of the gods.
In 1931 (the last Indian census to record caste), Brahmins accounted for 4.32% of the total population.
Brahmins even in Uttar Pradesh, where they were most numerous, constituted just 12% of the recorded population.
Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! They also took up various other professions since late vedic ages like doctors, warriors, writers, poets, land owners, ministers, etc.
Only a subset of brahmins were involved in the priestly duties.
It is a misunderstanding that brahmins are only priests.