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    <p>You can break your <code>string</code> into two pieces to clarify things:</p> <pre><code>string = '\\' + '\'' </code></pre> <p>Each part is a string of length one; <code>'\\'</code> is the single character <code>\</code> and <code>'\''</code> is the single character <code>'</code>. When you put them together you get the two character string <code>\'</code>.</p> <p>There are two characters that are special within a single quoted string literal: the backslash and the single quote itself. The single quote character is, of course, used to delimit the string so you need something special to get a single quote into a single quoted string, the <em>something special</em> is the backslash so <code>'\''</code> is a single quoted string literal that represents a string containing one single quote character. Similarly, if you need to get a backslash into a single quoted string literal you escape it with another backslash so <code>'\\'</code> has length one and contains one backslash.</p> <p>The single quote character has no special meaning within a double quoted string literal so you can say <code>"'"</code> without any difficulty. The backslash, however, does have a special meaning in double quoted strings so you have to say <code>"\\"</code> to get a single backslash into your double quoted string.</p> <p>Consider your guess off <code>"\'"</code>. The single quote has no special meaning within a double quoted string and escaping something that doesn't need escaping just gives you your <em>something</em> back; so, if <code>c</code> is a character that doesn't need to be escaped within a double quoted string, then <code>\c</code> will be just <code>c</code>. In particular, <code>"\'"</code> evaluates to <code>"'"</code> (i.e. one single quote within a double quoted string).</p> <p>The result is that:</p> <ul> <li><code>'\\\'' == "\\'"</code></li> <li><code>"\\\"" == '\\"'</code></li> <li><code>"\'" == '\''</code></li> <li><code>"\'" == "'"</code></li> <li><code>'\\\''.length == 2</code></li> <li><code>"\\\"".length == 2</code></li> <li><code>"\'".length == 1</code></li> <li><code>"'".length == 1</code></li> </ul> <p>The <a href="http://en.wikibooks.org/wiki/Ruby_Programming/Strings">Wikibooks reference</a> that Kassym gave covers these things.</p> <p>I usually switch to <a href="http://en.wikibooks.org/wiki/Ruby_Programming/Syntax/Literals#The_.25_Notation"><code>%q{}</code> (similar to single quoting) or <code>%Q{}</code> (similar to double quoting)</a> when I need to get quotes into strings, all the backslashes make my eyes bleed.</p>
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    1. COThat is an excellent explanation; thanks to the both of you for the link. I agree with you also, I think the %q{}/%Q{} option is best for quotes, as it's easier to read.
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