smartypants can perform the following transformations:
* Straight quotes (" and ') into "curly" quote HTML entities
* Backticks-style quotes (``like this'') into "curly" quote HTML entities
* Dashes (-- and ---) into en- and em-dash entities
* Three consecutive dots (... or . . .) into an ellipsis entity

This means you can write, edit, and save your posts using plain old ASCII
straight quotes, plain dashes, and plain dots, but your published posts (and
final HTML output) will appear with smart quotes, em-dashes, and proper
ellipses.

smartypants does not modify contents in some HTML element. Typically, these
tags are used to display text where smart quotes and other "smart punctuation"
would not be appropriate, such as source code or example markup.