A smart-quotes plugin.
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 characters within &lt;pre&gt;, &lt;code&gt;, &lt;kbd&gt;, &lt;math&gt; or &lt;script&gt; tag blocks. 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.