Greek beta, before that Phoenician beth — "house".
B
beth is the same word as the Hebrew for house, the one inside Bethlehem, "house of bread". The two bumps of B were once a floor plan.
Bailey · Baker · Bakker · Barker · Barnes · Bauer · Baxter · Becker · Bell · Bennett · Berry · Bevan · Bianchi · Black
In the modern alphabet this letter is number 2 of 26. Before it comes A, after it C. The order itself is inherited: Latin took it from Greek, Greek from Phoenician, and the sequence has survived largely unchanged for about three thousand years. Every rearrangement since has been an insertion, not a reshuffle.
This is a consonant: it sets the hardness of a name and how it meets the next word. In a corpus of 315 surnames this letter opens 27 and closes 1. Among the 96 given names in the base it appears in 10. The surname carrying the most of it is Webb, with 2.
Robert · Jacob · Benjamin · Elizabeth · Barbara · Isabella · Brian · Bruce · Rebecca · Deborah
These letters came from the Greek alphabet.