by Mignon Fogarty
The ampersand (&) is a symbol for and. Unlike the percent or degree symbol, you generally shouldn't use the ampersand except in the most informal situations.
Some style guides allow ampersands as part of a formal company name (Smith & Wesson, Tiffany & Co.). Other style guides recommend spelling out the and in such cases. Most style guides recommend using the ampersand when the rest of the name is also an abbreviation (AT&T) and in common expressions (R&D). As you see here, there are no spaces on either side of the ampersand when it is used that way.
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