Welcome to our journey through JavaScript's for loops - powerful tools for automating repeatable tasks. Using simple examples, we'll explore the For Loop, For-In Loop, and For-Of Loop. Let's get started!

Essentially, loops execute tasks repeatedly, akin to playing a favorite song on repeat. Here's a simple for loop that prints numbers from 1 to 5:

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1for (let i = 1; i <= 5; i++) {
2    console.log(i); // Will print numbers from 1 to 5
3}
4/*
5Prints:
61
72
83
94
105
11*/

In this example, we initialize i as 1, set our condition as i <= 5, and increment i by 1 in each iteration with i++. So, i goes from 1 to 5, and every time, we print the current value of i to the console.

Note: i++ is an increment operation that increases the value of i by 1. It basically the same as i = i + 1 or i += 1, just in a shorter form.

Let's look at our example once again:

JavaScript
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1for (let i = 1; i <= 5; i++) {
2    console.log(i); // Will print numbers from 1 to 5
3}

The For Loop comprises three elements:

• Initialization: Here, i starts at 1.
• Condition: The loop persists as long as i <= 5.
• Changes: Here, i++ increases i by 1 each loop iteration.
  • Changes can be anything, we could also decrease i by 1 every time if that would make more sense.

The structure of the loop is always as follows:

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1for ([initialization]; [condition]; [changes]) {
2    [loop body]
3}

Consider, for instance, how we might list all seven days of the week:

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1let days = ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday'];
2for (let i = 0; i < days.length; i++) { // 'i' goes through all 'days' list indices
3    console.log(days[i]); // Prints each day of the week onto the console
4}
5/*
6Prints:
7Monday
8Tuesday
9Wednesday
10Thursday
11Friday
12Saturday
13Sunday
14*/

A for-in loop iterates over properties of an object, similar to checking items in a backpack:

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1let star = {
2    name: "Sun",
3    color: "Yellow",
4    size: "Giant",
5};
6for (let property in star) {
7    console.log(property, '->', star[property]);
8}
9/*
10Prints:
11name -> Sun
12color -> Yellow
13size -> Giant
14*/

In this example, property steps through each property in the star object, and star[property] retrieves the value for each property.

The for-of loop processes iterable objects like arrays or lists. Imagine a daily task list:

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1let planets = ['Mercury', 'Venus', 'Earth', 'Mars', 'Jupiter', 'Saturn', 'Uranus', 'Neptune'];
2for (let planet of planets) { // iterate through all planets in the list
3    console.log(planet); // Prints every planet onto the console
4}
5/*
6Prints:
7Mercury
8Venus
9Earth
10Mars
11Jupiter
12Saturn
13Uranus
14Neptune
15*/

Here, planet traverses all the elements in planets, printing each one. Note that when using for-of, you don't need an index in the list - you iterate through the elements of the list themselves.

Excellent work! You have now mastered JavaScript for, for-in, and for-of loops. These integral building blocks will enable you to write clean and efficient code.

Coming up next, you will sharpen these skills in practical exercises. Practice is crucial to reinforcing the knowledge you've acquired. Best of luck!