Data Structures

How you store and manipulate data.

Maps

Completion Percentage: 95% (20592)
Completion Percentage: 95% (20592)
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The Map object holds key-value pairs and remembers the original insertion order of the keys. MDN

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Sets

Completion Percentage: 94.8% (20546)
Completion Percentage: 94.8% (20546)
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The Set object lets you store unique values of any type, whether primitive values or object references. MDN

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Typed Arrays

Completion Percentage: 94.7% (20536)
Completion Percentage: 94.7% (20536)
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JavaScript typed arrays are array-like objects that provide a mechanism for reading and writing raw binary data in memory buffers. MDN

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Array.prototype.flat()

Completion Percentage: 95% (20603)
Completion Percentage: 95% (20603)
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The flat() method creates a new array with all sub-array elements concatenated into it recursively up to the specified depth. MDN

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