Explain filter() in javascript with example and output

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The filter method in JavaScript is a powerful array method that creates a new array containing only elements that pass a specific test. It takes a callback function that returns true or false for each element. Let's see how it works with a visual example. Let's walk through a practical example step by step. We start with an array of numbers from 1 to 10. We want to filter out only the even numbers using the modulo operator. Watch as we test each element one by one. Filter is versatile and works with different data types. You can filter strings by length, filter objects by properties, or use arrow function syntax for cleaner code. Each example shows how the callback function determines which elements pass the test. Remember these key points about filter: it never changes the original array, always returns a new one, and the callback must return true or false. You can chain filter with other array methods like map for powerful data transformations. Let's see how method chaining works step by step. To summarize what we've learned: The filter method is a powerful tool for creating new arrays containing only elements that pass your test. It never modifies the original array, works with any data type, and is essential for clean, functional programming in JavaScript.