Beta

About

Beta is the second letter of the Greek alphabet. In the system of Greek numerals, it has a value of 2. In Ancient Greek, beta represented the voiced bilabial plosive IPA: [b]. In Modern Greek, it represents the voiced labiodental fricative IPA: [v], while IPA: [b] in borrowed words is instead commonly transcribed as μπ. Letters that arose from beta include the Roman letter ⟨B⟩ and the Cyrillic letters ⟨Б⟩ and ⟨В⟩.

Summary from Wikipedia