# Prime marks and typography

Lately I've been working with some geographical data and some of this requires representation in metric units and some in imperial units.

Something I had seen but didn't really know how to search for was the correct typesetting to use for feet and inches. It turns out that this is supposed to be done with a prime character and not an apostrophe. Thanks to widespread unicode adoption we have the following unicode code points we can use:

- U+2032 ′ PRIME (
`′`

) (`lower case p`

) - U+2033 ″ DOUBLE PRIME (
`″`

) (`upper case P`

) - U+2034 ‴ TRIPLE PRIME (
`‴`

) - U+2035 ‵ REVERSED PRIME (
`‵, ‵`

) - U+2036 ‶ REVERSED DOUBLE PRIME
- U+2037 ‷ REVERSED TRIPLE PRIME
- U+2057 ⁗ QUADRUPLE PRIME (
`⁗`

) - U+02B9 ʹ MODIFIER LETTER PRIME
- U+02BA ʺ MODIFIER LETTER DOUBLE PRIME

So something like three feet and eight inches should be typeset like this: 3′8″