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    <p>Both are just methods called on objects. This means that the objects decide which means what. However, there are conventions in Ruby about how these are different. Usually, <code>==</code> is stricter than <code>===</code> - <code>a === b</code> will <i>almost</i> always be true if <code>a == b</code> is. The best place to read about this is <a href="http://ruby-doc.org/core/classes/Object.html" rel="noreferrer">http://ruby-doc.org/core/classes/Object.html</a>. Scroll down to the different sections about <code>==</code> and <code>===</code>. Here are some of the conventions I know about:</p> <ul> <li><code>==</code>, when applied to plain <code>Object</code>s, will only be true if one is exactly the same as the other - if they are stored in the same memory location (this is how Ruby works internally). If the arguments are of types other than Object, though, this method will usually be overridden.</li> <li><code>equal?</code> is just like <code>==</code> for plain <code>Object</code>s, but will never be overridden by subclasses.</li> <li><code>===</code> is used for: <ul> <li>an <code>is_a?</code> alternative, backwards. <code>String === 'str'</code> is true.</li> <li>matching regexes. <code>/s[at]r*/ === 'str'</code> is true.</li> </ul></li> </ul> <p>You can find the specific meaning of <code>===</code> for various classes in the documentation for those classes, for example, the <code>Range</code> version is here (a synonym for <code>include?</code>): <a href="http://ruby-doc.org/core/classes/Range.html#M000691" rel="noreferrer">http://ruby-doc.org/core/classes/Range.html#M000691</a></p>
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    1. PORuby comparison operators? == vs. ===
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    1. COA good example of overriding `==` so that it does what you (probably) expect is strings. Compare `==` and `.equal` for a string literal and a variable pointing at the "same" string.
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