What are the performance differences between arrays and objects in JavaScript?

What are the performance differences between arrays and objects in JavaScript?

In JavaScript, arrays are optimized for numerical indexing and are generally faster for operations like push and pop. Objects, on the other hand, are better for key-value pairs and can be more efficient for lookups.

Can you give me an example where one is better than the other?

Sure! If you're storing a list of items where order matters, use an array. For example, a list of user IDs. If you need to store user details with unique keys, like usernames, an object is more suitable.

How does the size of the data affect performance?

As the size of the data increases, arrays can become slower for certain operations like searching, while objects may handle lookups more efficiently due to their hash table implementation.

Are there any best practices for choosing between them?

Yes! Use arrays for ordered collections and when you need to perform operations like map or filter. Use objects for unordered data and when you need to access properties by name.