Why shouldn't `'` be used to escape single quotes?
escaping, html, quotes
Solution
`"` is on the official list of valid HTML 4 entities, but `'` is not.
From C.16. The Named Character Reference ':
The named character reference `'` (the apostrophe, U+0027) was introduced in XML 1.0 but does not appear in HTML. Authors should therefore use `'` instead of `'` to work as expected in HTML 4 user agents.
Problem
As stated in, When did single quotes in HTML become so popular? and Jquery embedded quote in attribute, the Wikipedia entry on HTML says the following: The single-quote character ('), when used to quote an attribute value, must also be escaped as `'` or `'` (should NOT be escaped as `'` except in XHTML documents) when it appears within the attribute value itself. Why shouldn't `'` be used? Also, is `"` safe to be used instead of `"`?