In Js, Some piece of codes are repeatative and need to call frequently.

We can not write same lines of code multiple times. if we do then its hard to change or debug all together.
to avoid this issue, there are many Loops to use in js.

Loops are repeaters. it repeats the line of code as we need.

Instead of this,

        console.log("Hello");
        console.log("Hello");
        console.log("Hello");
        console.log("Hello");
        console.log("Hello");
     

We can write it as this,

        for (let i = 0; i < 5; i++) {
            console.log("Hello");
        }
     

Types of Loops

◈ for Loop

Use when you know how many times to repeat.

Let's take above example,

        console.log("Hello");
        console.log("Hello");
        console.log("Hello");
        console.log("Hello");
        console.log("Hello");
    ▶

We can write this as,

        for (let i = 0; i < 5; i++) {
            console.log("Hello");
        }
    ▶

this is most simple way to get repeatative output.

◈ While loop

Use when: We repeat until something happens .
This is conditional loop

Let's take above example,

        let num = 0;
        while (num < 3) {
          console.log(num);  // 0, 1, 2
          num++;
        }
    ▶

        0
        1
        2
    

These are the most simple way to get repeatative output.

◈ do...while Loop

Use when you want the code to run at least once before checking the condition.

Let's take the same "Hello" example using do...while:

        let i = 1;
        do {
            console.log("Hello");
            i++;
        } while(i <= 5);
    ▶

Lets Make this more simple.

◈ for Loop

✅ Use when you know how many times to repeat.

• Best for fixed number of repetitions.
• Example: printing 10 tickets

        for(let i = 1; i <= 10; i++) {
            console.log("Ticket #" + i);
        }
    

◈ while Loop

🔁 Use when you don’t know how many times to repeat, but have a condition to stop.

• Good for repeating until a task is done.
• Example: keep asking user to guess number

        let guess;
        while(guess !== 5) {
            guess = prompt("Guess the number:");
        }
    

◈ do...while Loop

👌 Use when you want to run code at least once before checking the condition.

• Always runs the block once.
• Example: show menu at least once

        let choice;
        do {
            choice = prompt("1. Start\n2. Help\n3. Exit");
        } while(choice !== "3");