<ul><li>In JavaScript, primitive values like numbers, strings, and booleans are copied when passed into functions.</li><li>The function works with a copied version of the primitive, leaving the original value unchanged.</li><li>Passing primitives to functions ensures that changes made inside the function do not affect the original value.</li><li>JavaScript sets aside new memory space for copies of primitives during function calls.</li><li>Primitives provide predictability as their values don't change unless intentionally reassigned.</li><li>On the other hand, objects and arrays are passed by reference in JavaScript functions.</li><li>When objects or arrays are passed, both the original variable and the function parameter share the same underlying object.</li><li>Changes made to objects or arrays inside a function reflect outside because they operate on the same shared memory location.</li><li>Passing objects or arrays into functions can lead to unexpected changes if not handled carefully.</li><li>While passing by reference may introduce surprises, it also allows JavaScript to handle complex data structures efficiently.</li></ul>

How Values Get Passed in JavaScript Functions

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