Conditional Statements (if, else if, else)

Har program ko aakhirkar value ke hisaab se alag alag kaam karne parte hain. JavaScript is ke liye if, else if, aur else istemal karta hai — curly braces se har block mark hota hai, Python ki indentation ke bar-aks.

let age = 20;
if (age >= 18) {
  console.log("You are an adult");
} else {
  console.log("You are a minor");
}

You are an adult

=== vs. ==

JavaScript mein do equality operators hain, aur inka farq waqai ahmiyat rakhta hai: === value aur type dono ek sath check karta hai (strict equality), jabke == compare karne se pehle types convert kar deta hai (loose equality), jo hairat angaiz results de sakta hai.

console.log(5 === 5);
console.log(5 === "5");
console.log(5 == "5");

true
false
true

Hamesha === istemal karo jab tak koi khaas wajah na ho. == khamoshi se "5" aur 5 ko equal bana deta hai, jo shayad hi kabhi aap asal mein chahte ho, aur subtle bugs ka aam sabab hai.

else if se conditions ko jorna

let score = 75;
if (score >= 90) {
  console.log("A");
} else if (score >= 80) {
  console.log("B");
} else if (score >= 70) {
  console.log("C");
} else {
  console.log("F");
}

C

JavaScript har condition ko upar se neeche check karta hai aur jo pehli condition true milti hai wahin ruk jaata hai — score >= 70 else tak pohanchne se pehle hi match ho jaata hai, isliye "C" print hota hai aur uske baad sab skip ho jaata hai.

Aage: for loops — collection ke har item par code ko dohrana.