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A front-end web developer is responsible for implementing visual elements that users see and interact with in a web application. They are usually supported by back-end web developers, who are responsible for server-side application logic and integration of the work front-end developers do.
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Typescript vs. Javascript in 2021
TypeScript is a relatively new programming language that first appeared about 8 years ago. It is developed by Microsoft and is a superset of JavaScript. This means that anything that you do with JavaScript can be done with TypeScript as well. But what sets TypeScript apart from JavaScript? We will take a look at this from a TypeScript point-of-vie...
Introduction to JavaScript Variables and Assignment
In this lesson, we will discuss basic elements in programming, with a focus on the following key points: What are variables and the assignment of variables in a programming language? Working with variables and assignment of variables in JavaScript. _This lesson is intended for web and fronten...
Initializing Variables and Basic Math Operations
In this lesson, we will discuss the use of variables in programming, with a focus on the following key points: What are variables, and how are they used in a computer program? Learn to work with math operations in JavaScript. _For the Python version of this lesson, [please click here] (https:/...
What are Strings and String Operations?
In this lesson, we will discuss one of the basic types in programming languages, with a focus on the following key points: What are strings and common string operations? Working with strings in JavaScript. _For the Python version of this lesson, [please click here] (https://algodaily.com/lessons...
Introduction to Arrays and Array Operations
In this lesson, we will discuss the concept of arrays, with a focus on the following key points, What are arrays, and how are they implemented? Working with array operations in JavaScript. For the Python version of this lesson, [please click here] (https://algodaily.com/lessons/introduction-array...
Control Flow: If/Else and Try/Catch Statements
Understanding Program Execution Flow: Mastering Control Statements Key Objectives In today's lesson, we delve into the crucial topic of program execution flow. We'll concentrate on answering two fundamental questions: How can you manipulate the execution sequence of a program? How do if/else and try...
Loops and Iterations in Programming
In this lesson, we will learn about loops and iterations in programming, with a focus on the following key points, What are iterations in programming? Working with loops and related concepts in JavaScript. For the Python version of this lesson, [please click here] (https://algodaily.com/lessons/l...
Calling Functions: Calling, Parameters, Returning
In this lesson, we will learn about functions in a program, with a focus on the following key points, What are functions, and why do we use them? Working with function parameters, return, and call statements. For the Python version of this lesson, [please click here] (https://algodaily.com/lesso...
Objects and Key-Value Stores
In this lesson, we will learn about a new type of data structure called objects, with a focus on the following key points, What are objects and how are they used? Working with objects and key-value pairs in JavaScript. For the Python version of this lesson, [please click here] (https://algodaily....
Higher Order Functions in Javascript
A function is a chunk of code intended to reduce code repetition and enhance code quality. JavaScript, a function-based programming language, leverages higher-order functions to integrate the concept of abstraction. Today, we will discuss the concept of higher-order functions in JavaScript and how to use them effectively. However, let's f...
Classes and Objects in JavaScript and TypeScript
In everyday life, we can list a thing's qualities and attributes whenever we have to describe it. For example, describing a certain book involves specifying its title, publication year, ISBN, author, and the number of pages. This collection of information comes together and helps specify an instance of a book This concept also ex...
Find Minimum And Maximum Value In An Array Using JavaScript
How To Find Minimum And Maximum Value In An Array Using JavaScript In this challenge you are going to learn how you can get the maximum and the minimum value of an array using JavaScript. First of all we need an array. What is an Array? In JavaScript, an array is an ordered list of values. Each value is called an element specified by a...
How to Filter an Array of Objects in JS
Before we start discussing this topic, let's do a quick revision of both arrays and objects. At a very high level, arrays are collections of similar things. A common example you might think of is a six-pack of beer. The entire "thing" - the six-pack itself, is an array. Each individual can of beer...
Javascript Build Tools and Bundlers
What are JavaScript build tools and bundlers? JavaScript build tools and bundlers are software applications that help you automate the process of building, bundling, and minifying JavaScript code. Build tools can also help you with other tasks, such as transpilation, code splitting, and hot reloading. **Why are they importan...
Hoisting and Call Stack
Understanding Variable Scoping in JavaScript Let's dig into a fascinating JavaScript example to unravel the mystery of variable scoping. The Code Snippet Here's the code we'll be examining: var numOfBeers = 5; function getMoreBeers() { console.log('I have this many beers: ' + numOfBeers); var numOfBeer...
Closures and Dependency Injection
In JavaScript, closures and dependency injection are powerful concepts that enable modular, maintainable, and flexible code. In this challenge, you will explore these concepts by implementing a specific functionality using closures and then using closures for dependency injection. Part 1: Closures Closures allow...
Get Data Type
Detecting JavaScript Data Types: A Universal Method The Challenge Imagine a universe of data types in JavaScript! It's a colorful world with characters like Array, ArrayBuffer, Map, Set, Date, and the mysterious Function. Your mission, should you choose to accept it, is to create a universal method that identifi...
Implement Promise.all
According to the MDN docs, the Promise.all() method "takes an iterable of promises as an input, and returns a single Promise that resolves to an array of the results of the input promises". It is useful when there is a collection of promises that you need to resolve prior to some other code execution work that neeeds to be done. H...
Implement Array.shuffle
Shuffling an array is an operation that generates a random inline permutation of the elements of a given array. Can you implement a shuffle method, that will accept one parameter - the array to shuffle, and will shuffle its elements in a random order? An example of how your method should work, would be to generate one of the poss...
Implement Throttling
Both debouncing and throttling are intended to enhance a website's performance. They accomplish this primarily by limiting the number of times a function can execute. In the case of throttling, the exact definition is that it's a technique where a function can be executed only once in any given time interval-- **regardless of how...
Create Curry Function
In mathematics and computer science, currying is the technique of converting a function that takes multiple arguments into a sequence of functions that each takes a single argument. Currying provides a way for working with functions that take multiple arguments, and using them in frameworks where functions might take onl...
Implement JSON.parse
In JavaScript by default, there is a method that can parse a given JSON string, and it can be invoked by calling JSON.parse(). The way this method works is constructing the JavaScript value or object described by the string. Can you implement your own version of this method, called parseJSON, accepting one parameter (the JSON...
Create Event Emitter
In modern applications, we often need asynchronous functions. These wait for responses from operations with unknown completion times. So many frameworks use an event-driven architecture. Certain objects called emitters emit named events. This triggers listener functions to execute. Each event has an ID. So listeners know wh...
Implement Instance Of
In Object-Oriented programming, an instance represents an object which is an instantiation of a class. An object can also be an instance of a given class A if it is instantiated from a class B that extends the class A. In a non-programming context, you could think of "cat" as a class and your particular cat as an instance o...
Implement JSON.stringify
In Javascript there is a method called JSON.stringify() that can convert an object or a variable into a JSON string. The method handles different data types differently, ending up with its correct JSON "translation". Some examples of how this method handles different types include: Boolean, Number, and String object...
Implement ClearAllTimeouts
Mastering Time Control in Browsers with window.clearAllTimeouts Imagine you have the power to control time in your browser. You can schedule events to happen in the future and even cancel them before they occur. This is exactly what window.setTimeout() and window.clearTimeout() allow you to do! Scheduling a Future Ev...
Create Browser History
Every modern browser has implemented a logic for keeping track of the users' browsing history. Usually, it keeps track of the websites visited, and their order, so the user can be able to go back and forth between their recently visited websites. Can you implement a simplified version of a browser history tracker, that will keep...
Create a Pipe Method
Composition is putting two or more different things together, and getting a combination of the inputs as a result. In terms of programming, composition is often used for combining multiple functions and getting a result at the end. Using composition leads to a cleaner and much more compact code. If we want to call multiple f...
Implement Array.reduce
In JavaScript there is a built-in method called reduce() that can be used over the Array prototype. What this method does, is that it executes a user-supplied "reducer" callback function on each element of the array, in order, passing in the return value from the calculation on the preceding element. The final result of ru...
Implement Array.flat
In Javascript there is a method for flattening an array that can be invoked by calling the function flat(array, depth). This function works in such a way that it reduces the nesting of a given array, by creating a new array with all sub-array elements concatenated into it recursively up to the given depth level. This means tha...
