Explain every() in javascript with example and output

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Welcome to JavaScript's every method! The every method is a powerful array method that tests whether all elements in an array pass a provided test function. It returns true only if every single element passes the test, and false if any element fails. Let's see how it works with a simple example. Let's trace through the execution step by step. The every method starts with the first element, 2, and checks if it's greater than 0. It passes! Then it moves to 4, which also passes. Next is 6, which passes too. Finally, 8 also passes the test. Since all elements passed the condition, every returns true. Now let's see what happens when not all elements pass the test. Consider the array with values 1, 2, negative 3, 4, and 5. The every method checks 1 greater than 0, which is true. Then 2 greater than 0, also true. But when it reaches negative 3, the test fails! At this point, every immediately stops checking and returns false, without even looking at the remaining elements 4 and 5. Here's the complete JavaScript code example. First, we create an array with all positive numbers: 1, 2, 3, 4, 5. We call every with a function that tests if each element is greater than 0. Since all elements pass, it returns true. In the second example, we have a mixed array with 1, 2, negative 3, 4, 5. When every encounters negative 3, it immediately returns false without checking the remaining elements. To summarize what we've learned about JavaScript's every method: It tests all elements in an array against a provided condition. It returns true only if every single element passes the test. If any element fails, it immediately returns false and stops checking the remaining elements. This early stopping behavior makes it efficient for performance. The every method is perfect for validation scenarios where you need to ensure all items meet specific criteria.