know/your/slashes

a)    ⁄            b)  /          c)  \
slashes are named for the direction they lean as read in english (i.e. the two leaning to the right are forward and the third slash is leaning left, or backward)

for the uninitiated there are two different forward leaning slashes and they serve separate purposes.

symbol a) is called a solidus, shilling mark, or in-line fraction bar and its uses are just what they sound like. old british currency notation (pounds⁄shillings⁄pence) used the symbols £⁄s⁄d which you notice do not correctly initialize their namesakes. this is because they were taken from the roman currency units of the libra, the solidus, and the denarius. old macintosh keyboards had a key for this symbol, but modern typists are much more likely to settle for...

...symbol b), which is referred to as a slash, stroke, virgule, diagonal, forward slash, right-leaning stroke, oblique dash, slant, separatrix, scratch comma, slaok, over, slak, whack, and sometimes mistakenly as a backslash or solidus. this symbol stands more upright than a true solidus.

some history via wikipedia:

in the Middle Ages, one slash (/) represented a comma, while two slashes (//) represented a dash. The two slashes eventually evolved into a sign similar to the equals sign (=), then being further simplified to a single dash or hyphen (–).

 this slash type is by far the most common, being used for all the following reasons and more:

• related words/phrases
• line breaks/in a poem
• abbreviations (r/c for radio control, w/e for whatever)
• substitute for division or fractions when the solidus is not easily accessible (3/5)
• a bowling spare
• /drive/folder/file locations or web://url's
• special chat commands (e.g. /me, /joinchannel, /refreshbnet)
• dates (9/24/09)
• phonemic pronunciation guides e.g. next post ;-)
  
• gender neutrality in spanish and portugese (senor/a)

symbol c), named backslash, reverse solidus, oblique, slosh, hack, escape, reverse slash, backslant, backwhack, bash, reverse slant, reversed virgule, or backslat, is the mirror image of the forward slash and is used almost exclusively in computing as a sort of flag (e.g. escape characters, TeX markup tag, line continuations for viewing long lines on a small screen) and windows paths (both c:/ and c:\ are acceptable, but c:\ is official)