The Latin B's sound and its Phoenician root are covered elsewhere in this atlas; this entry follows its shape. Phoenician bet, meaning house, was drawn as a simple angular floor plan, little more than a vertical stroke with an open triangle. Greek beta straightened this into two stacked triangular lobes on a vertical stem, a form still visible in the modern capital Beta.
Etruscan and early Roman scribes rounded those triangles into the two bows familiar today, and by the time of classical Roman inscriptions the capital B had already reached essentially its current shape, with the lower bow customarily drawn slightly larger than the upper for visual balance, a convention type designers still follow. The lowercase b emerged later, through Roman cursive and then uncial handwriting, which extended the letter's left stroke upward into an ascender while keeping only the lower bow as a closed loop; that ascender-plus-bowl structure, fixed by the Carolingian minuscule of the 9th century, is the direct ancestor of the lowercase b in every printed and digital typeface used today.
Blackletter and Fraktur hands, used in German-language printing into the 20th century, gave the capital B a markedly more angular, broken-stroke form than the rounded shape common elsewhere in Europe, a divergence type historians treat as a separate branch of the letter's graphic family rather than as a competing origin.