# Introduction In this lab, we will explore the implementation of a JavaScript function that determines the size of an array, object, or string. Through this lab, you will learn how to identify the type of a given value and determine its size using various techniques such as the `Array.prototype.length` property, the `length` or `size` value, and the number of keys for objects. By the end of this lab, you will have a better understanding of how to work with different data types in JavaScript.
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