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Node.js Functions - Callbacks

Callbacks are functions that are passed as arguments to other functions and are called when an operation is complete. Callbacks are the most basic form of asynchronous programming in Node.js.

function add(a, b, callback) {
    var sum = a + b;
    callback(sum);
}

add(2, 3, function(result) {
    console.log(result); // prints 5
});

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