freeCodeCamp/guide/english/certifications/javascript-algorithms-and-data-structures/basic-javascript/modify-array-data-with-indexes/index.md

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Modify Array Data With Indexes

Modify Array Data With Indexes

Access the position of the array, and change it, like so:

var arr = [1, 2, 3, 4, 5];
    
arr[0] = 6; // Now, the array is [6, 2, 3, 4, 5]
arr[4] = 10 // Now, the array is [6, 2, 3, 4, 10]

The important concept here is that arrays are mutable. This means that they can be changed easily.