Escape escapes special characters like "<" to become "<". It
escapes only five such characters: <, >, &, ' and ".
UnescapeString(Escape(s)) == s always holds, but the converse isn't
always true.
Unescape unescapes entities like "<" to become "<". It unescapes a
larger range of entities than EscapeString escapes. For example, "á"
unescapes to "á", as does "á" and "á".
Unescape(EscapeString(s)) == s always holds, but the converse isn't
always true.