Ever wondered why there is a ‘|’ symbol on your keyboard? I have, and I finally found out how it got there a few days ago.
(slightly edited)
The SHARE IBM users' group opposed the adoption of ASCII-1967 because the vertical bar, which is the PL/I logical OR operator, appears in a section of the code reserved for "national use" characters, and, moreover, in the lower case section of the code which might not be supported by all devices.
SHARE insisted that there be a vertical bar in the uppercase, international section of the code, so the X3.2 subcommittee made it acceptable to substitute a vertical bar symbol for the exclamation point, and broke the character that was supposed to be a vertical bar in half so it could not be mistaken for a logical OR symbol. The damage was repaired in ASCII-1977, but by this time large numbers of devices were using the broken-bar symbol and the transition back to the real, solid, international, vertical bar is still not complete.
I had thought perhaps it had something to do with logic (boolean OR), and it turns out I was right. Ever wondered why it is often seen as a broken bar on many keyboards? It was done in order to disassociate it from the OR symbol. It still doesn't make particular sence as to why they did this to me though.
I have previously asked another, very knowledgeable person (ROK), and he thought it may have been an overstike mark, that you could use to create characters such as ¢, or ‘⊥’; or a form of negation, to create characters such as ‘≮’. While these are possible (and possibly auxiliary motives), most special characters are on the keyboard today because they were used by the programming languages of the time, such as COBOL.
BTW, the symbol ‘∣’ is also used in mathematics for integer ‘divides by’.