Updated: 02/07/2022 by Computer Hope
Yellow rectangle with B: characters in black lettering

B may refer to any of the following:

1. B: is a floppy disk drive letter used on MS-DOS and Windows-based computers most associated with the 5.25-inch floppy disk drive, and sometimes the 3.5-inch floppy formats. Today, it's rare for a computer to be using a B: drive, as both floppy formats are obsolete. Also, the hard drive defaults to the C: drive. However, it is still possible to assign any drive as the B: drive.

2. In programs dealing with text like a word processor, an icon of a "B" may be shown to represent bold.

3. The B programming language is a programming language developed at Bell Labs in 1969 by Ken Thomson and Dennis Ritchie. The language was based on BCPL, and "B" is likely a shortening of that name. Although the B language is no longer used, it led to the development of the C programming language, which is still widely used today.

4. B is a key used with the keyboard shortcuts Alt+B, Command+B, and Ctrl+B.

5. The letter "b" is also chat slang for "be" or "bee."

6. With a regular expression, \b is word boundary in most languages or a backspace. When capitalized, \B is a non word boundary.

7. With Microsoft Excel and other spreadsheet programs, "B" is the second column of a spreadsheet. To reference the first cell in the column, you'd use "B1."

8. In the phonetic alphabet, "B" is often pronounced as "bravo."

9. B is the second letter of the English alphabet. The letter "B" comes after "A" and is followed by the letter "C." To create a capitalized "B" press the Shift and B key at the same time.

On a U.S. QWERTY keyboard, the "B" key is on the bottom row, to the right of "V" and left of the "N" key. See our keyboard page for a visual example of all keyboard keys.


If the "B" key is not working on the keyboard, see: Some of the keys on my computer keyboard aren't working.


In ASCII the uppercase "B" is "066" in decimal (01000010 in binary). The lowercase "b" is "098" in decimal (01100010 in binary).

A:, C:, Drive letter, Floppy drive, Floppy drive terms, Letter