Less typing, cleaner syntax, and the modern way to write JavaScript functions.

The first time I saw an arrow function, I thought someone had accidentally deleted half the code. No function keyword? No curly braces? No return statement? And it still works ?

const square = n => n * n ;

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That's a complete, working function. It takes a number, squares it, and returns the result. Compare that to the traditional version:

function square ( n ) { return n * n ; }

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Same behavior, half the characters. Arrow functions were introduced in ES6 (2015), and they've become the default way to write functions in modern JavaScript. In the ChaiCode Web Dev Cohort 2026, they show up in almost every lesson — callbacks, array methods, event handlers, React components.…