Summary  
The `filter` method creates a new array containing only the elements for which a provided callback returns true, preserving the original array (immutability) and enabling chaining with other array methods for concise data transformations.

General domain of usage  
Filtering data sets in collections (e.g., extracting subsets based on criteria)

The `filter` method is a **powerful tool** in JavaScript for creating a new array that includes only those elements from an existing array that satisfy a specific condition. When you use `filter`, you provide a **callback function** that tests each element. If the callback returns `true` for an element, that element is included in the new array; if it returns `false`, the element is excluded. This makes `filter` especially useful for extracting **subsets of data**, such as finding all users over a certain age, selecting completed tasks, or narrowing down items based on search criteria.

const numbers = [1, 2, 3, 4, 5, 6];
const evenNumbers = numbers.filter(function(num) {
  return num % 2 === 0;
});
console.log(evenNumbers); // Output: [2, 4, 6]

One important aspect of `filter` is that it does not modify the original array. Instead, it returns a new array containing only the elements that passed the test. This concept is called **immutability**. By leaving the original array unchanged, `filter` helps prevent unexpected side effects in your code, making it easier to reason about data flow and transformations.

> Note
>
>You can also chain `filter` with other array methods, such as `map` or `sort`, to perform more advanced transformations in a single, readable line of code. This makes it easy to build complex data processing pipelines while keeping your code clean and expressive.

Which of the following will be the output of the code below?

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Filtering Arrays with filter

1. Which of the following will be the output of the code below?

2. Complete the callback function to filter an array of numbers, returning only those greater than 10.