The ampersand is the logogram "&", representing the conjunction word "and". It originated as a ligature of the letters et, Latin for "and".
USAGE: Ampersands are commonly seen in business names formed from partnership of two or more people, such as Johnson & Johnson, Dolce & Gabbana, Marks & Spencer, and Tiffany & Co., as well as some abbreviations containing the word and, such as AT&T (American Telephone and Telegraph), R&B (rhythm and blues), B&B (bed and breakfast).
The ampersand can be used to indicate that the "and" in a listed item is a part of the item's name and not a separator (e.g. "Rock, pop, rhythm & blues, and hip hop").
The ampersand may still be used as an abbreviation for "and" in informal writing regardless of how "and" is used.
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