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‫So Merge Sort is going to be our first sorting algorithm that uses recursion and it leverages the idea

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‫that if you have two sorted arrays like this, these are two sorted arrays.

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‫Combining two sorted arrays is fairly easy.

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‫So what merge sort does is this let's mix this up like this and move this to the top of the screen so

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‫we have more room.

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‫It will take this array and it will cut it in half.

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‫And then it will cut it in half again.

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‫And then it'll keep doing this until we have single item arrays.

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‫Because a single item array is by definition sorted.

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‫Then what we can do is take two of these.

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‫And combine them into one larger sorted array.

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‫And then we continue doing this all the way across like this.

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‫Then we'll take these two arrays.

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‫And combine them and then we'll combine those two.

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‫Now we can take these two sorted arrays and make one big sorted array out of these.

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‫When you first look at this, you think, wow, that looks really inefficient to break all of this down

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‫into single item arrays.

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‫But it is actually an incredibly efficient sorting algorithm.

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‫It's as efficient as you can make a sorting algorithm, actually.

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‫So that is our quick overview.

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‫Of merge sort.