I was reading a style guide and encountered a section about the slash (/). This reminded me of a pet peeve, which I will mention here in the hope that it may change the behavior of some readers.
The slash (solidus, virgule, etc.) has been around for a long time. The backslash (reverse solidus, reversed virgule, etc.) is of more recent vintage, a product of the computer age. “Backslash” became a commonly used word as a result of its use in MS-DOS.
Unfortunately, people got so used to saying “backslash” when talking about their computers, they began saying “forward slash” when referring to a slash. This is redundant.
The Wikipedia entry for “virgule” calls “forward slash”a retronym. (Interested readers might want to look at the Wikipedia entry, as well as the Wikipedia entry for “backslash.”) It is a retronym, of course, but it is an unnecessary one. “Film camera” is a useful term to distinguish a particular device from a digital camera. It is only needed because we have come to call any device that takes pictures a camera. “Slash,” on the other hand, has not become a generic term for either a solidus or a reverse solidus.
The only reason to use “forward slash,” I assert, is in certain situations where there are references to each character in close proximity. For example, this sentence might be reasonable: ALGOL allows the symbol for logical-or to be represented by a backslash followed by a forward slash. Even this sentence looks a bit odd, since, by analogy, we might expect to see “forwardslash.”
So, here is my rule: The "/" character is a slash; the "\" character is a backslash.