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Ways of looping through Arrays in ES5:
```javascript
let array = [1,2,3];
```
### Clasic for loop
```javascript
for (let i = 0; i < array.length; i++) {
console.log(array[i]);
}
```
### Array.forEach method
```javascript
array.forEach(function (value) {
console.log(value);
});
```
Downsides:
- You can’t break out of this loop using a break statement or move to the next iteration with continue.
- You can’t return from the enclosing function using a return statement.
### For In
The for-in loop is designed for iterating over an objects properties, like so:
```javascript
var obj = {a:1,b:2};
for (let prop in obj) {
console.log(prop); //prints a, b
}
```
If we tried to use it with an array:
```javascript
let array = [10,20,30];
for (let index in array) {
console.log(index); // prints '0', '1' ... converts the index to a string
});
```
In ES6 we have a new syntax:
### For Of
The for–of loop is for looping over the values in an array. It also works on most array-like objects including the new Set and Map types.
```javascript
let array = [10,20,30];
for (var value of array) {
console.log(value); // prints 10, 20, 30
}
```
- This is the most concise way of looping through array elements.
- It avoids all the pitfalls of for–in.
- It works with break, continue, and return
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