People sometimes get the backslash (\) confused with the slash (/) (see this xkcd item). If this ever happens to you, remember that the slash is the normal ordinary slash that you’ve seen in ordinary writing outside computers — 1/2, and/or, w/o, and the like. (You can call it a virgule if you’d like, and if you don’t care whether people understand you.) The backslash is that, but backwards.
Why people call slashes backslashes, I don’t know, but my one guess is that “backslash” sounds more interesting and important, and thus sucks people in through its weird charisma. In any event, slash is just the normal slash, as in 1/2; backslash is the other one.
Of course, if one day enough people start calling a slash a backslash, then this will become a standard meaning of “backslash,” and things will be confused. But that day hasn’t yet come, and with luck never will, since the slash-backslash distinction, confusing as it is some, remains quite useful, and no easy alternative is available.