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copied!<p>In C you can't define the function inline, so you can't really create a closure. All you're doing is passing around a reference to some pre-defined method. In languages that support anonymous methods/closures, the definition of the methods are a lot more flexible.</p> <p>In the simplest terms, function pointers have no scope associated with them (unless you count the global scope), whereas closures include the scope of the method that's defining them. With lambdas, you can write a method that writes a method. Closures allow you to bind "some arguments to a function and getting a lower-arity function as a result." (taken from Thomas's comment). You can't do that in C.</p> <p>EDIT: Adding an example (I'm going to use Actionscript-ish syntax cause that's what's on my mind right now):</p> <p>Say you have some method that takes another method as its argument, but doesn't provide a way to pass any parameters to that method when it's called? Like, say, some method that causes a delay before running the method you passed it (stupid example, but I want to keep it simple).</p> <pre><code>function runLater(f:Function):Void { sleep(100); f(); } </code></pre> <p>Now say you want to user runLater() to delay some processing of an object:</p> <pre><code>function objectProcessor(o:Object):Void { /* Do something cool with the object! */ } function process(o:Object):Void { runLater(function() { objectProcessor(o); }); } </code></pre> <p>The function you're passing to process() isn't some staticly defined function anymore. It's dynamically generated, and is able to include references to variables that were in scope when the method was defined. So, it can access 'o' and 'objectProcessor', even though those aren't in the global scope.</p> <p>I hope that made sense.</p>

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