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copied!<p>At a low level, there is no such thing as a multi-dimensional array. There is just a flat block of memory, large enough to hold a given number of elements. In C, a multi-dimensional array is conceptually an array whose elements are also arrays. So if you do:</p> <pre><code>int array[2][3]; </code></pre> <p>Conceptually you end up with:</p> <pre><code>array[0] => [0, 1, 2] array[1] => [0, 1, 2] </code></pre> <p>This results in the elements being arranged contiguously in memory, because <code>array[0]</code> and <code>array[1]</code> are not actually holding any data, they are just references to the two inner arrays. Note that this means that only the <code>[0, 1, 2]</code> entries actually occupy space in memory. If you extend this pattern out to the next dimension, you can see that:</p> <pre><code>int array[2][3][2]; </code></pre> <p>...will give you a structure like:</p> <pre><code>array[0] => [0] => [0, 1] [1] => [0, 1] [2] => [0, 1] array[1] => [0] => [0, 1] [1] => [0, 1] [2] => [0, 1] </code></pre> <p>Which continues arranging the elements consecutively in memory (as above, only the <code>[0, 1]</code> entries actually occupy space in memory, everything else is just part of a reference to one of these entries). As you can see, this pattern will continue no matter how many dimensions you have.</p> <p>And just for fun:</p> <pre><code>int array[2][3][2][5]; </code></pre> <p>Gives you:</p> <pre><code>array[0] => [0] => [0] => [0, 1, 2, 3, 4] [1] => [0, 1, 2, 3, 4] [1] => [0] => [0, 1, 2, 3, 4] [1] => [0, 1, 2, 3, 4] [2] => [0] => [0, 1, 2, 3, 4] [1] => [0, 1, 2, 3, 4] array[1] => [0] => [0] => [0, 1, 2, 3, 4] [1] => [0, 1, 2, 3, 4] [1] => [0] => [0, 1, 2, 3, 4] [1] => [0, 1, 2, 3, 4] [2] => [0] => [0, 1, 2, 3, 4] [1] => [0, 1, 2, 3, 4] </code></pre>

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