P3.3: JS Functions & Scope

Functions are blocks of reusable logic. Scope determines the accessibility of variables declared in the code.

1. Declaring Functions

Functions are created using declarations or modern ES6 arrow expressions:

// Classic Declaration
function add(a, b) {
  return a + b;
}

// ES6 Arrow Function (Prevalent in React)
const multiply = (a, b) => a * b;

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“Functions are the building blocks of abstraction. Understand how functions closure works—they remember the variables of the scope they were created in.”