Inspired by a Tweet by Garr Reynolds, I dug up the typography rules for apostrophes and quotation marks. The ' and " that everybody is using because they are conveniently located on a computer keyboard are in fact the characters for feet and inches.
- ‘ and ’ - the single quotation marks (the right one is the apostrophe), ASCII codes 145 and 146
- “ and ” - the double quoation marks, ASCII codes 147 and 148
- ALT+code (Windows only). Swith on your numeric keypad with NUMLOCK (laptop owners read your manual). Hold down the ALT key, now press "0" plus the ASCII code you need on the numeric keypad, the number keys on top of the regular keyboard will not work. For example, an apostrophe would be [ALT]  [release ALT]
- HTML option 1, for example to display the apostrophe enter ’ (for more ASCII codes see above)
- HTML option 2, enter & followed by a specific character code, a full list can be found here. Single open: ‘ Single close: ’ (apostrophe) Double open: “ Double close: ”
Because of the complicated entry, I double check use of quotation marks only in final versions of presentation documents. In email, Twitter, (and even in this blog...), I will continue to violate the rules and use my feet and inches characters... Sorry. Some other relevant links
- Microsoft Office (including PowerPoint), I use the insert symbol menu option, switch to ASCII decimal code and find the right symbols at position 145-148
- More info about quotation mark typography, plus the full set of codes for the Apple can be found here.
- I am not getting into the subject of grammar, but if you are interested check Wikipedia
- An amusing set of pictures (including the embedded one) can be found in this blog that is devoted to the subject in its entirety