What is JavaScript?

Summary

This video provides an insightful introduction to JavaScript, answering key questions such as what JavaScript is, its uses, where it runs, and the difference between JavaScript and ECMAScript. The video highlights JavaScript's popularity, its applications in web and mobile development, and the role of Node.js in running JavaScript outside of browsers. Additionally, it explains ECMAScript's role in standardizing JavaScript features. The tutorial includes a practical demo of writing JavaScript code in the Chrome console, offering a hands-on learning experience for viewers.

Takeaways

• 🌐 JavaScript is a highly popular programming language used globally and is experiencing rapid growth.
• 📈 Major companies like Netflix, Walmart, and PayPal use JavaScript to build internal applications, offering significant job opportunities for developers.
• 💰 JavaScript developers in the United States have an average salary of $102,000 per year, making it a lucrative career choice.
• 🔄 JavaScript can be used for front-end, back-end, and full-stack development, offering versatility in web development roles.
• 🚀 JavaScript was initially used for building interactive web pages but now supports building full web and mobile apps, real-time networking applications, command-line tools, and games.
• 🖥️ JavaScript code runs in browsers using JavaScript engines like SpiderMonkey (Firefox) and V8 (Chrome), but it can also run outside browsers using Node.js.
• 🔧 Node.js is a C++ program embedding the V8 JavaScript engine, allowing JavaScript to be used for server-side development.
• 🌍 JavaScript can execute in two main environments: browsers and Node.js, both providing a runtime environment for the code.
• 📜 ECMAScript is a specification that JavaScript adheres to. JavaScript is a language that conforms to ECMAScript standards.
• 📅 ECMAScript 2015 (ES6) introduced many new features for JavaScript, with yearly updates following since 2015 by the standards body ECMA.
• 🖱️ Developers can easily test JavaScript code in the browser's developer console by using commands like `console.log('Hello World')` and `alert('Yo')`.

Q & A

What is JavaScript?

JavaScript is one of the most popular and widely used programming languages in the world. It's growing faster than any other programming language and is used by big companies like Netflix, Walmart, and PayPal for building internal applications.

What can you do with JavaScript?

JavaScript can be used to build interactive web pages, full-blown web or mobile apps, real-time networking applications like chats and video streaming services, command-line tools, and even games.

Where does JavaScript code run?

JavaScript code can run inside browsers or in Node.js. Browsers have JavaScript engines that execute the code, such as SpiderMonkey in Firefox and V8 in Chrome. Node.js, a C++ program that includes Google's V8 JavaScript engine, allows JavaScript code to run outside of browsers.

What is the difference between JavaScript and ECMAScript?

ECMAScript is a specification, while JavaScript is a programming language that conforms to this specification. ECMAScript is defined by an organization called ECMA, which releases annual updates to the specification, such as ECMAScript 2015 (ES6).

Why is JavaScript referred to as a toy language by some developers?

JavaScript was initially used only in browsers to build interactive web pages, leading some developers to consider it a toy language. However, due to community support and investments by companies like Facebook and Google, JavaScript's capabilities have expanded significantly.

How did Node.js change the use of JavaScript?

Node.js, created by Ryan Dahl in 2009, embedded Chrome's V8 JavaScript engine inside a C++ program. This allowed JavaScript to run outside of browsers, enabling the development of backend applications for web and mobile apps using JavaScript.

What tools do you need to write JavaScript code?

For a quick demo, you can use the JavaScript console in a browser's developer tools. For real-world applications, you would set up a development environment with tools like Node.js, a code editor, and possibly other frameworks and libraries depending on the project.

What are some examples of JavaScript engines in browsers?

Examples of JavaScript engines in browsers include SpiderMonkey in Firefox and V8 in Chrome. These engines execute JavaScript code within the browser.

What does the 'console.log' function do in JavaScript?

The 'console.log' function in JavaScript is used to print messages to the JavaScript console. It's commonly used for debugging purposes to check values and outputs of expressions.

What is the significance of ECMAScript 2015 (ES6)?

ECMAScript 2015 (ES6) introduced many new features and improvements to JavaScript, such as arrow functions, classes, template literals, and more. It marked a significant update to the language and set the standard for future developments.

Outlines

00:00

🔍 Introduction to JavaScript

The speaker introduces the video as a 3-minute session addressing four common questions about JavaScript: What is JavaScript, what can you do with it, where does JavaScript code run, and what is the difference between JavaScript and ECMAScript. JavaScript is highlighted as a highly popular and rapidly growing programming language, used by major companies like Netflix, Walmart, and PayPal for internal applications. The potential for high salaries and diverse job roles (front-end, back-end, or full-stack developer) is also mentioned.

05:02

🛠️ Uses of JavaScript

JavaScript was historically used only in browsers to create interactive web pages, often dismissed as a 'toy language.' However, its capabilities have expanded significantly due to community support and investments from large companies like Facebook and Google. Nowadays, JavaScript can be used to build web and mobile apps, real-time networking applications like chats and video streaming services, command-line tools, and even games.

🌐 Where JavaScript Runs

JavaScript was initially designed to run exclusively in browsers, with each browser having its own JavaScript engine (e.g., SpiderMonkey in Firefox and V8 in Chrome). In 2009, Ryan Dahl created Node.js by embedding Chrome's V8 engine into a C++ program, allowing JavaScript to run outside of browsers. This means JavaScript can now be used for backend development as well. JavaScript code can run inside browsers or Node.js, both providing runtime environments for it.

📝 JavaScript vs. ECMAScript

ECMAScript is a specification, while JavaScript is a programming language that conforms to this specification. The organization responsible for ECMAScript, Ecma International, defines standards for the language. ECMAScript's first version was released in 1997, and since 2015, new versions have been released annually. ECMAScript 2015 (also known as ES6) introduced many new features to JavaScript.

🚀 JavaScript in Action

The speaker demonstrates how to write and execute basic JavaScript code in a browser. By opening Chrome, inspecting the page, and using the console tab, users can run JavaScript commands directly. Examples include logging 'Hello World' to the console, performing basic arithmetic, and displaying alerts. This segment serves as a quick demo, with a promise of more detailed instruction in subsequent lectures on setting up a development environment for JavaScript.

📚 Further Learning

The speaker, Mashar, briefly mentions that this tutorial is part of a comprehensive JavaScript course covering essential concepts and featuring numerous exercises and solutions. The course offers a certificate of completion, and interested viewers can find more information in the video description. The next section of the tutorial will continue to provide valuable content on JavaScript.

Keywords

💡JavaScript

JavaScript is a popular and widely used programming language. It is essential for creating interactive web pages and applications. In the video, JavaScript is described as being utilized by major companies like Netflix, Walmart, and PayPal for internal applications.

💡Front-end developer

A front-end developer is responsible for creating the visual and interactive aspects of a website that users engage with directly. The video mentions that learning JavaScript can lead to a job as a front-end developer, emphasizing the language's importance in web development.

💡Back-end developer

A back-end developer works on the server-side of web applications, handling databases, server logic, and application integration. JavaScript, through environments like Node.js, allows developers to build the back-end of web and mobile applications.

💡Full stack developer

A full stack developer is skilled in both front-end and back-end development, capable of creating a complete web application. The video highlights that mastering JavaScript can enable one to become a full stack developer, handling all aspects of an application's development.

💡JavaScript engine

A JavaScript engine is a program that executes JavaScript code. Examples include SpiderMonkey in Firefox and V8 in Chrome. The video explains that these engines allow JavaScript to run in browsers, and with Node.js, JavaScript can also run outside of browsers.

💡Node.js

Node.js is a runtime environment that allows JavaScript to be executed on the server-side. It was created by embedding the V8 JavaScript engine in a C++ program. The video mentions that Node.js enables JavaScript to build back-end services and run outside the browser.

💡ECMAScript

ECMAScript is a specification for scripting languages, with JavaScript being one of the most well-known implementations. The video discusses how ECMAScript defines the standards that JavaScript follows, with updates and new features being released periodically.

💡ES6

ES6, or ECMAScript 2015, is a version of the ECMAScript standard that introduced many new features to JavaScript. The video notes that ES6 brought significant improvements to the language and is a key point in JavaScript's development history.

💡Console

The console is a developer tool available in web browsers that allows developers to write and test JavaScript code directly in the browser. The video demonstrates using the console to execute basic JavaScript commands like 'console.log' and 'alert'.

💡Alert

The 'alert' function in JavaScript creates a pop-up message in the browser. The video uses 'alert' as an example to show how JavaScript can produce immediate, visible effects in a web page by displaying a message to the user.

Highlights

JavaScript is one of the most popular and widely used programming languages in the world right now.

Big companies like Netflix, Walmart, and PayPal build internal applications around JavaScript.

The average salary of a JavaScript developer in the United States is about $120,000 a year.

You can work as a front-end developer, back-end developer, or a full-stack developer with JavaScript knowledge.

JavaScript was initially used only in browsers to build interactive web pages.

JavaScript can now be used to build full-blown web or mobile apps, real-time networking applications, command-line tools, and even games.

JavaScript was originally designed to run only in browsers with engines like SpiderMonkey (Firefox) and V8 (Chrome).

Node.js, created by Ryan Dahl, allows JavaScript to run outside of browsers by embedding the V8 engine in a C++ program.

With Node.js, JavaScript can be used to build the backend for web and mobile applications.

JavaScript code can run inside a browser or in Node.js, which provide runtime environments for JavaScript code.

ECMAScript is a specification, while JavaScript is a programming language that conforms to this specification.

ECMAScript is managed by an organization called ECMA, which defines the standards for JavaScript.

The first version of ECMAScript was released in 1997, with annual releases starting from 2015.

ECMAScript 2015 (ES6) introduced many new features for JavaScript.

Using Chrome's developer tools, you can write and execute JavaScript code directly in the console.

This tutorial is part of a complete JavaScript course that includes exercises, solutions, and a certificate of completion.

Transcripts

[Music]

in the 3-minute introduction I'm going

to answer for frequently asked questions

about JavaScript

what is JavaScript what can you do with

it where does JavaScript code run and

what is the difference between

JavaScript and echo script so let's

start with the first question what is

JavaScript JavaScript is one of the most

popular and widely used programming

languages in the world right now it's

growing faster than any other

programming languages and big companies

like Netflix Walmart and PayPal build

internal applications around javascript

and here's the average salary of a

JavaScript developer in the United

States and it's only $2,000 a year so

it's a great opportunity to get a good

job out of learning JavaScript you can

work as a front-end developer or a

back-end developer for a full stack

developer who knows both the front end

and the back end now the second question

what can you do with JavaScript for a

long time

javascript was only used in browsers to

build interactive web pages some

developers refer to javascript as a toy

language but those days are gone because

of huge community support and

investments by large companies like

Facebook and Google these days you can

build full-blown web or mobile apps as

well as real time networking

applications like chats and video

streaming services command-line tools or

even games here's an example a third

question where does JavaScript code run

javascript was originally designed to

run only in browsers so every browser

has what we call a JavaScript engine

that can execute JavaScript code for

example the JavaScript engines in

firefox and chrome are SpiderMonkey and

v8 in 2009 a very clever engineer called

Ryan Dahl took the open-source

JavaScript engine in chrome and embedded

it inside a C++ program he called that

program node the node is a C++ program

that includes Google's v8 JavaScript

engine now with this we can run

JavaScript code out

of a browser so we can pass our

JavaScript code to node for execution

and this means with JavaScript we can

build the backend for our web and mobile

applications so in a nutshell JavaScript

code can be run inside of a browser or

in node browsers and node provide a

runtime environment for our JavaScript

code and finally the last question what

is the difference between JavaScript and

Eggman script well ECMO script is just a

specification javascript is a

programming language that confirms to

this specification so we have this

organization called a comma which is

responsible for defining standards they

take care of this Eggman script

specification the first version of

Eggman script was released in 1997 then

starting from 2015

ACMA has been working on annual releases

of a newest specification so in 2015

they released a kimono script 2015 which

is also called ECMO script version 6 or

es6 for short this specification defined

many new features for JavaScript alright

enough theory

let's see javascript in action so every

browser has a JavaScript engine and we

can easily write JavaScript code here

without any additional tools of course

this is not how we build real-world

applications but this is just for a

quick demo so open up Chrome right click

on an empty area and go to inspect now

this opens up chrome developer tools

here select the console tab this is our

JavaScript console and we can write any

valid JavaScript code here so type this

console dot log put a single code here

and then hello world another single code

to terminate close the parentheses and

add a semicolon at the end now as you go

through the course you're going to

understand exactly what all this means

for now don't worry about it so now I'll

press ENTER and you can see the hello

world message on the console we can also

write mathematical expressions here for

example two plus two we get four or we

can do something like this alert

practices single coat yo enter and

here's an alert in the next lecture I'm

going to talk about setting up your

development environment for writing

JavaScript code

well hello it's mahshar thank you for

watching my javascript tutorial I just

wanted to quickly let you know that this

tutorial is part of my complete

JavaScript course where you can learn

about all the essential concepts in

JavaScript the course is packed with

lots of exercises and solutions and by

the end of watching the course you will

also receive a certificate of completion

in case you're interested you can find a

link in the video description and if not

that's perfectly fine continue watching

as the next section is coming up