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JavaScript Asynchronous Programming with JavaScript Asynchronous JavaScript with Callbacks Implement a Callback

3 Answers

Karolin Rafalski
Karolin Rafalski
11,368 Points

Both .map() and .forEach()iterate over each item in an array.

.map() returns a new array that you can save into a new variable.

.forEach() goes over the array but doesn't save the changed values into a new array.

A for loop is a great choice and can accomplish both things that .map() and .forEach() can accomplish (most of the time - an exception would be if you were using the React library where you have to use .map() to accomplish certain things but that's a more advanced use-case).

Over time, as people get more comfortable with JavaScript/writing code, many people find .map() and .forEach() easier to read/understand what the code is trying to do and it's less likely you'll mistype: ie forgetting to put .length as part of the control panel of your for loop. There is also a for of loop, which also has a nice and easy to read syntax as well. But in most cases, it is a coding-style preference.

A for loop can be a better choice if you don't need to iterate over every item (ie just the odd items, or every third, the first half...)