Artturi Jalli

In JavaScript, the difference between the == operator and === operator is in how the comparison is made: A great way to see this is by comparing a number and a string that represents the same number: As it turns out, the == operator converts the comparables to a common type before making a comparison.

The main difference between let and var in JavaScript is: This means you can have multiple let variables with the same name as long as they live in different scopes, such as in different functions. For instance: In addition to this, there is a bunch of important differences, such as hoisting. These are important to

In JavaScript, the array is an extremely commonly used data type. You can use an array in a variety of tasks to store and access values with ease. Some common tasks you want to do with arrays include: And so much more. The Array data structure comes with a bunch of helpful built-in methods. You

In JavaScript, you can use a for loop to repeat a task based on a condition. As long as the condition is true, the looping continues. When the condition becomes false, the loop terminates. For example, let’s display numbers from 0 to 5 using a for loop: Output: In this particular for loop, the condition

In JavaScript, you can fold an array to a single value with the reduce() method. The reduce() method works such that it: The reduce() method accumulates the array of elements into a single cumulative value. For example, let’s calculate a sum of an array of numbers: Output: This is a great demonstrative example of how

In JavaScript, you can use the built-in Array.forEach() method to perform an action for each element. For instance, given an array of numbers, let’s print all the values one number at a time: Output: The forEach() method does not create a new array. Instead, it just performs an operation for each element. If you want

In JavaScript, you can use the Array.map() method to: For instance, given an array of numbers, let’s create a new array of the numbers squared: Output: This returns a new array with the original numbers squared. This is a comprehensive guide on how to use the map() method in JavaScript. You are going to learn

In JavaScript, semicolons are optional. Yes, you heard it right. However, there are some situations in which omitting a semicolon can lead to unwanted consequences. So there is no definitive answer as to whether you should use a semicolon or not. Using semicolons always causes a debate in the JavaScript community. There are good arguments

In JavaScript, objects are reference values. This means you cannot use the assignment operator (=) to clone objects. If you do, you are just creating an alias for the existing object. To clone a JavaScript object correctly, you have 4 different options: Here is a quick example of each approach: Important: But how do these