JavaScript is a popular programming language that was born in 1995, and is now core to the modern web. It’s a critical coding skill to learn if you want to get into web development. It’s also a versatile language that can unlock a variety of well-paid job opportunities that are experiencing rapid wage growth.
According to US News & World Report, software development ranked as the #1 job in 2023. These factors are based on growth potential, salary, employment rate, future job prospects, stress level and work-life balance. The number of software developers is expected to grow to 28.7 million by 2024 globally, a 12.5% increase from 2020. There are many job opportunities for JavaScript developers. One study found the median yearly salary in 2023 was $74,034 USD—up roughly 13% from $65,680 in 2022.
Salaries can also increase significantly as you gain more experience and advance into more senior developer positions. JavaScript is widely used, so learning it can unlock new opportunities that are remote or freelance.
Despite big promises from CEOs, flashy DEI hires and significant financial investments by companies, the tech industry continues to fall behind when it comes to diversity. While Black employees make up 12% of the US workforce, only 8% of tech workers are Black. Thanks to this gap, Black households may lose out on more than $350B in tech job wages by 2030, according to the McKinsey Institute for Black Economic Mobility.
Companies are still competing for tech talent, however many businesses continue to struggle with recruiting diverse employees. The root issue? Everyone is fishing in the same pond, competing for the same pool of talent.
Some companies have decided to pivot and pursue alternative approaches to recruiting underrepresented tech talent. Uber Design Pathways (UDP) Apprenticeship Program, for example, is a recent success story. Last summer, Uber first partnered with General Assembly to identify a group of high-potential, underrepresented San Francisco Bay Area residents interested in transitioning careers and provide them with the unique opportunity to embark on a future-proof UX career through the design apprenticeship.
If you’re tired of hearing about the tech talent shortage: buckle up. Tech layoffs may be making headlines, but the reality on the ground looks different for tech leaders. Tech talent continues to be in high demand, and short supply. According to Gartner, this will continue until at least 2026 based on forecast IT spend.
The threat of a potential recession has put significant pressure on CIOs, CDOs, CTOs and other technology leaders, who feel crunched to deliver returns on technology and data investments, streamline costs, and modernize business systems. Organizations that are ahead of the curve on digital transformation are more flexible and resilient, meaning they are better positioned to come out of an economic slowdown stronger.
Every industry today is a tech-driven industry, and without the right talent, it’s impossible to keep up. This widening gap between demand for tech talent and supply of tech talent is costing employers significantly as they compete for a small pool of candidates.
So what’s behind the persistent tech talent shortage? Three things that are within a company’s control:
Today’s talent market is undergoing a major shift, and organizations are rethinking their talent strategies. After a period of massive hiring and growth, some companies are taking a step back and reducing their workforce, such as through layoffs or hiring freezes. Many organizations are taking a more thoughtful approach to hiring, selectively filling only key roles. Other companies still in growth mode see this as an opportunity to recruit top talent in a tight job market. Yet all businesses have one thing in common during times of economic volatility: a desire to shore up and future-proof their workforce against whatever comes next.
While investments in employer branding and talent development efforts can easily fall to the wayside during economic slowdowns, companies that are in it for the long haul can’t afford to press pause. Here are three things to consider as you evolve your organization’s talent strategy in the face of uncertainty.
For more than a decade, business leaders have sounded alarms about the shortage of tech talent, often using language more appropriate for the battlefield than for the boardroom. The Bureau of Labor Statistics predicts that demand for tech jobs, like software developers and data-related roles, will continue to grow rapidly over the coming decade. And recent research suggests that tech hiring has continued to trend upward as the country makes its way out of the pandemic.
For business leaders, the need to understand the evolving role of tech skills in the labor market has, in some ways, taken on renewed urgency in the wake of COVID-19. Facing a rocky road to economic recovery, policymakers and employers are in search of new strategies to not just get Americans back to work but also ensure that the country’s workforce is prepared to navigate a volatile and increasingly tech-driven economic landscape. The events of the past year have also cast a harsh light on the pervasive and painful equity gaps that have always been endemic in American society — and sparked new efforts to create economic mobility paths for workers who face systemic barriers to advancement and opportunity.
Against that backdrop, the demand for tech skills continues to spread across a range of industries. It’s a shift that presents opportunities and questions: What fields are seeing the greatest increase in demand for technology skills, and how can the needs of those fields be met? How do the perspectives of enterprise tech and talent leaders align with and respond to shifts in demand? How can a better understanding of what’s happening now help us understand what may happen in the future?
But despite – or, perhaps, because of – all this attention, the actual term “digital skills” is not always clearly defined. And trying to pin down a more precise definition is not always a straightforward task. In fact, the most important question to answer may be a more fundamental one: what do we mean by “digital skills” in the first place, and how do those skills manifest in today’s complex and volatile labor market?
To begin to answer some of these questions, we joined forces with Emsi Burning Glass to develop the Digital Talent Forecast, which draws on our unique collective viewpoints and taps into the real-time talent and skill needs faced by both employers and geographic regions at this time of economic change. The report incorporates original research from Emsi Burning Glass, as well as insights from our standards board members, to shed light on the present challenges and opportunities facing a labor market that is increasingly defined by digital skills.
Get a sneak peek of our findings by having a beer with Emsi Burning Glass below:
“Closure is the combination of a function bundled together (enclosed) with references to its surrounding state (the lexical environment).”
In simple terms, Closure is under functional programming, and it allows an inner function to access an outer function’s scope, even when the outer function has already returned.
Example:
const cartMode = function() {
let items=[] // acts like a private variable
function addItem(item) {
items.push(item)
return "Item added to Cart"
}
function totalItems() {
return items.length
}
return {
addItem,
totalItems
}
}
const cart=cartMode()
cart.addItem("Bag") // returns Item added to Cart
console.log(cart.items) // returns undefined
cart.totatItems() // returns 1
In the above example, the items variable is accessible to all the inner functions, but it’s not directly accessible from outside. This happens because of closures.
3. What is the difference between let, const, and var?
Before ES6, JS had no way to support block-level scope variables. Now, we have:
var for creating function-level scope variables.
let for creating dynamic block-level scope variables.
const for creating constant block-level scope variables.
Example:
var a = 20
if(a > 10) {
let b = 1
const a = 2
console.log(b,a, 'Inner Scope') // 1 2 Inner Scope
}
console.log(a, 'Outer Scope') // 20 Outer Scope
Even though we specified the delay as 0ms, it still prints “2” after “3.” This is because of the Event Loop in JavaScript.
In this case, first, console.log(“1”) is executed, then setTimeout() is executed; after the specified delay (in this case, 0ms), the callback function is added to Message Queue. Now the main thread only picks up items from the message queue once the current execution is done. So, the main thread first evaluates the console.log(“3”) statement post. Then, it picks up the callback() from the Queue and executes the console.log(“2”) statement. Hence, the above output.
5. The Difference between arrow functions and regular functions?
Arrow functions are new ES6 syntax for defining functions. It looks like this:
const add = (a,b) => a+b
add(2,3) // 5
The main difference between the arrow function and the regular function is the value of this keyword.
In the case of arrow functions, the keyword assigns a value lexically. What this means is unlike regular functions, arrow functions never create their own execution context. They, by default, take the execution context of the enclosing function, aka, parent.
Here is another great article explaining this in-depth.
Conclusion
Preparing for JavaScript Interviews can feel overwhelming, but you now know the JavaScript code, the programming language, and the scripting language; the only way to really answer an advanced JavaScript interview question is to examine things one concept at a time.
JavaScript (often shortened to JS) is a lightweight, interpreted, object-oriented language with first-class functions — it is best known as the scripting language for webpages. It is a prototype-based, multi-paradigm scripting language that is dynamic, and it supports object-oriented, imperative, and functional programming styles.
Now, what does all that mean?
Well, it could be a bit overkill to try to explain those topics if you are just starting out in coding or learning JavaScript. In short, JavaScript most often correlates with client-side scripting on webpages. When you use a website, anything you interact with usually involves JavaScript — a search bar on Google or a dropdown menu on Facebook is all JavaScript.
While JavaScript was originally intended for websites, its uses have far surpassed front-end interactive website usage. JavaScript can be used as a server side-language with NodeJS to create desktop and mobile apps or program different electronics (popular YouTuber, Michael Reeves, uses JavaScript on a lot of his quirky inventions). JavaScript has expanded immensely since its inception with tons of different use cases and massive community support.
The Best Places to Learn JavaScript
There are many ways to learn JavaScript — here are some of the best and the most cost-effective ways.
1. freeCodeCamp
With freeCodeCamp, everything runs in your browser. It has a code editor, console, and example browser window all within site. freeCodeCamp can seem daunting at first due to the sheer amount of content it has, but do not worry. If you are looking to learn JavaScript fast, it has a section called “JavaScript Algorithms and Data Structures Certification” specifically for JavaScript. It will take you through learning the basics of JavaScript and even some in-depth topics such as Data Structures and Algorithms.
Everything else freeCodeCamp has to offer is related to website programming. It even has sections on job hunting. If that is something you are interested in, I would recommend the entire site as it has a lot of great content. FCC also has a Youtube channel: youtube.com/c/freeCodeCamp, where it explains a lot of site topics in a video format.
2. Udemy/Youtube
I put these two in the same category since there is a lot of overlap, and you will see that a lot of people on Udemy use Youtube almost like a marketing tool for their full course. Nonetheless, a lot of Udemy courses range from $10–15 with a lot of good material. Really, one or two courses should be enough to learn JavaScript, so there is no need to spend a fortune. A few instructors I liked were Colt Steele and Brad Traversy.
Alternatively, both Colt Steele and Brad Traversy have Youtube channels that are free and have great content for learning JavaScript. Once you get the hang of the basics, I also recommend The Coding Train, which is run by Daniel Shiffman. I enjoyed all of these instructors’ teaching styles — they have great explanations for different concepts. That said, choose someone who best fits your needs and makes things clearest for you.
How to Learn JavaScript Fast
As with any language, learning JavaScript requires time, studying, and practice. I recommend you learn the basics, which include:
Variables
Types of Data: Strings, Integers, Objects, Arrays, Boolean, null, and undefined
Object Prototypes
Loops
If Statements/Conditionals
Functions
After you have those basics down, hop into some code challenges to get some practice. One site I would recommend is codewars.com. It has tons of challenges with varying levels of difficulty. Start at a basic level. Practice until you are comfortable with the above topics.
Another good practice exercise is making a game like tic-tac-toe or a basic calculator. With these exercises, you will be able to tackle different obstacles and exercise the syntax of JavaScript.
JavaScript Quick Tutorial
Variable Declaration
If the above materials are not enough, here is my quick JavaScript tutorial:
First, we have variables. In JavaScript, there are three ways you can declare a variable:
var: function-scoped.
let: block-scoped.
const: block-scoped, but cannot be reassigned; it also is initialized with an “a” value, unlike “var” and “let.”
Data Types
There are different data types, as mentioned above, but the most important is Objects. Objects are used for various data structures in JavaScript such as Array, Map, Set, WeakMap, WeakSet, Date, and almost everything made with a new keyword.
A small note about null: If you were to check the data type of null through JavaScript, it would evaluate to an Object. This is a loophole that has been utilized by programmers for years. This might not be very common for you early on…
Comments
Comments in JavaScript are signified with “//” for single-line comments or “/* ….. */” for longer blocks of comments. I bring this up now since the examples below have comments.
Loops
If you are not new to programming, I am sure you know what loops are. For those of you who are new to coding, loops are used to iterate or repeat a block of code a certain amount of times or until a condition is met. Loops are often used to go through items in an Array.
The most common loops are the traditional for loops and while loops. A lot of the following is from the developer.mozilla.org and MDN, which is similar to the documentation for JavaScript — here are some of the different loops JavaScript has to offer:
for loop:
for ([initialExpression]; [conditionExpression]; [incrementExpression]) {
// statement
}
Provided by MDN:
When a for loop executes, the following occurs:
The initializing expression, initialExpression, if any, is executed. This expression usually initializes one or more loop counters, but the syntax allows an expression of any degree of complexity. This expression can also declare variables.
The conditionExpression expression is evaluated. If the value of conditionExpression is true, the loop statement executes. If the value of the condition is false, the for loop terminates. (If the condition expression is omitted entirely, the condition is assumed to be true.)
The statement executes. To execute multiple statements, use a block statement ({ … }) to group those statements.
If present, the update expression incrementExpression is executed.
Control returns to Step 2.
An actual code example of a for loop:
for (let i = 0; i < array.length; i++) {
// code here
}
For loops are extremely useful and used often. It is very important to understand and master how for loops work.
do…while loop:
A do…while loop will run code until a condition is false
do {
// statement
}
while (condition);
while loop:
A while loop is very similar to the do while loop, but the key difference lies when the conditional is checked. In a do…while loop, the code block runs, and the condition is checked after the while loop checks the condition and runs the block of code.
while (condition) {
// statement
}
for…in loop:
For…in loop is used to loop over objects
for (variable in object) {
// statement
}
for…of loop:
For…of loop is used typically for arrays or iterable objects. I must stress using the correct loops for arrays and objects to avoid confusion.
for (variable of array) {
// statement
}
If Statements
If statements depend on whether a given condition is true and perform what is in the first set of the code block. Do not continue to evaluate the subsequent “else” portions. If there are subsequent conditions that need to be checked, the use of “if else” will be needed. If all conditions do not evaluate as true and there is an “else” provided, the “else” portion of the statement will be used.
if (condition) {
// statement1
} else if (condition2) {
// statement2
} else {
// statement3
}
Functions
There are two ways to write a function: a function declaration and a function expression. The “return” keyword is used in JavaScript to define what a function will return. All subsequent code below a return statement will not run inside a function.
Function Declaration:
function square(number) {
return number * number;
}
Function Expression:
var square = function(number) {
return number * number;
}
The key difference between the two is the function declarations load before any code is executed, while function expressions load only when the interpreter reaches that line of code.
Object Prototype/Classes
In order to provide inheritance, JavaScript utilizes things called prototypes.
Here is an example of what the syntax would look like:
function Person(first, last, age, gender, interests) {
// property and method definitions
this.name = {
'first': first,
'last' : last
};
this.age = age;
this.gender = gender;
//...see link in summary above for full definition
}
Creating a new instance of that prototype would look like this:
let person1 = new Person('Bob', 'Smith', 32, 'male', ['music', 'skiing']);
If you come from a different coding language, you may be more familiar with the term “classes.”
JavaScript also has something called classes — classes are built on prototypes:
class Person {
constructor(first, last, age, gender, interests) {
this.name = {
first,
last
};
this.age = age;
this.gender = gender;
this.interests = interests;
}
}
How To Run JavaScript
Since JavaScript is one of the core technologies of the Internet, every modern web browser will have built-in JavaScript consoles. There are also many web-based JavaScript compilers and interpreters.
Browsers
All the big-name browsers such as Chrome, Firefox, Safari, Internet Explorer, and Opera will have JavaScript consoles. I will explain the process on Google Chrome, but all the other browsers can be found in a similar fashion.
In Chrome, right-click anywhere in your browser window and select “Inspect.” Then click on the console tab. From there, you can write “JavaScript” right into the console. Another keyboard shortcut can be found by pressing Command + Shift + J on Mac and Control + Shift + J on Windows.
Web-Based
There are a lot of different web-based JavaScript consoles. My personal favorite is Repl.it, but other options include JS Bin, JSFiddle, and CodePen. Of course, if you find one that you are more comfortable with, you are welcome to use it.
Can I teach myself JavaScript?
The short answer is yes. I do truly believe you can learn JavaScript on your own, but as with anything, it will take time and discipline. There may be times when you want to quit, think you’ve had enough, or question if you are doing it correctly. My answer to those questions would be to follow the free options of Codecademy and freeCodeCamp (above) as they are very structured and give a good foundation for learning. Never get discouraged; you will be surprised at how much you actually know!
So… should I learn JavaScript or Python?
This is a loaded question and could be a whole article in itself, but it really comes down to use cases. Almost everything outside of the coding languages of JavaScript and Python is alike. This includes popularity, support, community, free and paid courses, and versatile uses.
If you are more interested in data analytics, artificial intelligence, and machine learning, Python may be the route to go. This is not to say you can only learn one language. If you are up for it, learn both! Python and JavaScript have evolved a lot since they were created, and both can be used for websites, data analytics, artificial intelligence, and machine learning.
You can run JavaScript console in terminal or any command-line interface using Node.js, an open-source, platform-agnostic runtime that executes JavaScript outside a web browser.
Before we take a deep dive into how to run JavaScript in browser, we need to understand few basic terminologies like:
Client-Side JavaScript
Server-Side JavaScript
Command Line Interface
Client-Side JavaScript
JavaScript code executed in the web browser is known as client-side JavaScript.
Client-side JS was originally used to add some interactivity on websites; for example, the Click on Submit button in a form sends form details to the server.
The <script>tag within your HTML page is used to write client-side JavScript, which is later executed by the browser.
When you run JS code outside the browser-like on a web server, it becomes server-side JavaScript.
Server-side JS is generally used to write the back-end logic of your web application; for instance, you can check to see if a user password matches the stored DB password.
You can run Server-side JavaScript using any command-line interface.
But, what is Command Line Interface, a.k.a.,Terminal?
CLI is a text-based interface that allows users to perform some operation in a computer by typing commands.
The most common CLI for popular OS’s are:
Windows: Command Prompt, PowerShell
Mac: Terminal, iTerm
Let’s see how to run JavaScript in these popular CLI’s:
Our lives today are dependent on the interactivity that JavaScript provides. If you want to really see how much you depend on it, you can disable JavaScript in your browser for a day. Some pages will load quicker, they’ll be cleaner, you’ll have less ads, no pop-ups, and the battery life of your computer may last longer. But also parts of the webpages simply will not work. Neither will Netflix, YouTube, Google Docs, Google Maps, and much more. We are, to a good degree, dependent on JavaScript to function. Today, virtually every computing device including iPhones, Android phones, MacOS, Windows, Linux, smart TVs, etc.. in the world have JavaScript interpreters installed on them and in active use.
It begins in the year 1995 at the Netscape headquarters, where young Brendan Eich goes into a ten day sprint of coding and comes out on the other side with a new language. Wow!
As more people used browsers to use and experience the internet, there was a need for a programming language that would give life to the browser. Something that went beyond HTML and CSS. That’s where JavaScript came in to give life to the browser. It’s a language that is capable of doing what all other programming languages do but also has a special relationship with the browser. It changed the way we thought about the internet and ushered a new era of browser based applications.
Easy setup
Unlike many other languages, where you need to go download the language in your machine in order to access all of its features and create a development environment, with JavaScript anyone with a web browser suddenly has a development environment right in front of them. Every browser supports JavaScript!
You can simply open your browser, like Chrome, and navigate to Developer Tools, and start coding away! To write a “Hello World” program is as simple as:
Event-based programming One of the most impressive features of JavaScript is that it includes event-based programming. It has built-in events like ‘onClick’ and ‘onHover’ that wait for user interaction on a website before executing a specific segment of code. For instance, when you click the night-mode toggle, that is an event which triggers a JavaScript code segment that changes the CSS across the whole website from light colors to dark colors.
JavaScript can be used to generate dynamic contents on a website as well. Different HTML tags can be generated based on user input. For instance, if you are on Facebook and you click into a comment box to type your comment on someone’s post, in that moment your click was an event that executed a code block in JavaScript that led to the generation of an HTML tag to display your comment.
End-to-end programming with Node.JS
While JavaScript has been given the title of The Language of the Browser, in 2009 with the release of Node.JS, a runtime environment that runs JavaScript code outside a web browser changed the fate of the language. Node.JS lets developers use JavaScript to write server-side scripting. Consequently, JavaScript’s popularity was dramatically increased because Node.JS represents the idea of “JavaScript everywhere” paradigm, unifying all of web application development around a single programming language, rather having a different language for server-side and client-side scripts.
In other words, now developers can use one single programming language to talk to databases, make HTTP requests, generate dynamic content, and create interactive user experiences/interfaces. This led to the Rise of Web Applications that we are experiencing today. In addition to having a unified web-application development, JavaScript also became the go-to language for many companies because now the engineering teams only had to worry about a single programming language which made it easier to debug and save costs in the overall development process.
In 2013 AirBnb launched their site and became the first to utilize the full-stack JavaScript solution. This approach allowed for code to be executed on the server-side and rendered in the browser with subsequent actions being handled by the exact same code on the client side. This inspired several other companies to do the same and today we have products and services like LinkedIn, Netflix, Uber, PayPal, eBay, Groupon, GoDaddy, CitiBank and many more using Node.JS.
JavaScript Libraries and Frameworks
The popularity of JavaScript led to the creation of several libraries and frameworks that have made application development efficient and performant. Today, libraries like React JS, jQuery, D3.js, etc.. are used in most applications across the world. Frameworks such as Angular, Ember JS, and Vue JS provide optimal performance and organization to build large applications.
Active Community
Amongst the programming languages, JavaScript has one of the largest communities according to Stackoverflow. In addition to that community, Node.JS has over a billion downloads across the world and is one the most widely used technologies.
These are just a few of the reasons why JavaScript is so popular. With the change in paradigm that led to the rise of web applications, unifying the web application development, cross browser support, and the plethora of libraries/frameworks available, the world of the internet has been fully invested in the growth of JavaScript. Furthermore, since JavaScript is a high-level interpreted language that is easy to understand, it is the one of the best languages to learn if you want to enter the world of programming and explore the amazing possibilities of web-application development.
