The letter "Bb" is the second letter of the English alphabet. It is a consonant and is pronounced as "bee." In the English language, "B" can represent various sounds, such as in the words bat and ball. In addition to its use in writing, "B" is also used in grading systems, where it typically signifies good performance, just above a C. In music, "B" refers to a specific note, and in chemistry, it can represent the element boron.