Course Overview

Overview of history of the JavaScript language

History of JavaScript

Overview of the relationship between JavaScript and Java

JavaScript vs Java

Overview of how JavaScript is evolved as a programming language

How is it evolved?

Overview of how we can track upcoming features in the JavaScript language

How to track upcoming features?

Overview of how the ECMAScript is versioned

How is ECMAScript versioned?

Explanation of whether JavaScript is interpreted or a compiled language

Is it interpreted or compiled?

Explanation of how JavaScript is executed

How is it executed?

Execution Context

Explanation of what is a callstack and how it is used in JavaScript

Callstack

Overview of memory management in JavaScript

Memory

What is JavaScript

What is hoisting?

Explanation of common misconception about hoisting in JavaScript

Misconception about hoisting

Hoisting

What is scope?

Explanation of global scope in JavaScript

Global scope

Explanation of function scope in JavaScript

Function scope

Block scope

Explanation of module scope in JavaScript

Module scope

Scope chain

Scope

What is coercion?

Diving into inner details of  coercion in JavaScript

Deeper look at coercion

Explanation of what abstract operations are and common types of abstract operations in JavaScript

Abstract operations

Explanation of how abstract or loose equality works in JavaScript

Abstract equality operator

Explanation of how the addition operator works in JavaScript

Addition operator

Explanation of how relational operators work in JavaScript

Relational operators

Coercion exercise for testing and practicing the knowledge learned in this module

Coercion exercise

Coercion

What is a closure?

Explanation of a common misconception about closures in JavaScript

Misconception about closures

Explanation of the problem of closures inside loops and how to fix it

Closures inside loops

Explanation of closures can be used to hide data

Data hiding using closures

Closures

What is prototypal inheritance?

Prototype chain

__proto__ property

Explanation of how we can create objects with custom prototypes in JavaScript

Custom prototypes

Explanation of how prototype chain is set with ES6 classes

ES6 classes and prototypes

Prototypes

Explanation of this keyword in JavaScript

What is this?

Explanation of how "this" works inside arrow functions

Arrow functions and "this"

Explanation of how value of "this" can be set explicitly

Explicitly binding "this"

globalThis

Summarizing "this"

'this' keyword

What is a symbol?

Explanation of why symbols were added in JavaScript

Why symbols?

Symbols and privacy

Explanation of global symbols in JavaScript

Global symbols

Explanation of what well-known symbols are in JavaScript

Well-known symbols

Symbol

Overview of asynchronous behavior of JavaScript

Overview

Overview of how callbacks help us write asynchronous code in JavaScript

Callbacks

Event loop

Promise

Explanation of promise chaining in JavaScript

Promise chaining

Explanation of some static methods of promises and their use cases

Use cases for static Promise methods

Explanation of async-await syntax in JavaScript

async await

Explanation of microtasks, how they are processed, and how they are linked to promises

Microtasks

Explanation of common anti-patterns to avoid when using promises in JavaScript

Promise anti-patterns

Asynchronous JavaScript

Explanation of what is an iterator in JavaScript

Iterators

Explanation of what is a generator in JavaScript

Generators

Explanation of how we can create asynchronous iterators in JavaScript

Asynchronous iterators

Explanation of how we can create asynchronous generators in JavaScript

Asynchronous generators

Iterators and Generators

Overview of what is debugging and different ways to debug JavaScript

Debugging

Overview of using the "debugger" statement to debug JavaScript

Debugger statement

Overview of using the breakpoints in browser developers' tools to debug JavaScript

Breakpoints in browser

Overview of using the VS Code debugger to debug JavaScript

VS Code debugger

Debugging JavaScript

Final thoughts and advice regarding how to continue the exciting journey of learning JavaScript

Conclusion

Wrap up

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( the primaryDescriptionMarkdown is long - several lines, include images, as long as you want )

In this course we <headline of what we do>. <why this technology is good> but <here's how learning it is problem>. 

In <the length of these lessons> we cover <three salient points about what we cover. Your BEST points>. Its <however long it is> and comes with <these bonus features, and reasons to buy. code, etc.>

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We created a free course to create your first GraphQL server (from scratch) using Node and TypeScript. TypeScript and GraphQL are a powerful combo, but there's a lot of confusing edges if you're getting it setup the first time.

In this course we cover the basics of getting TypeScript setup with Node, how GraphQL works, and how to set up a GraphQL server using Apollo server. It's two hours long, it comes with complete code examples, and we walk through the code step-by-step.

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In this course we <headline of what we do>. <why this technology is good> but <here's how learning it is problem>. 

( the summary is short - one or two lines )

Advanced JavaScript Unleashed

Within Ecma International, people responsible for developing the JavaScript language are part of the 

 (TC39). This committee consists of different stakeholders from the JavaScript community. Mostly people from big companies like Google, Microsoft, etc. are part of this group.

Other people can become part of TC39 as well and make their contribution in the development of the JavaScript language. Details of how anyone can either contribute or be part of TC39 meetings as a member can be found on the 

 which hosts multiple repositories related to their work. Repositories include notes from TC39 meetings, different proposals for the JavaScript language, details of how TC39 works, etc.

TC39 has a well-defined process through which proposals are passed before they can be added to the ECMAScript specification and ultimately be part of the JavaScript language.

Each proposal is passed through five stages which are mentioned below:

The first stage represents someone's idea that they think is worthy of being part of the JavaScript language.

Not all proposals at this stage move to the next stage, but the ones that do are the ones that gain enough interest and have a TC39 committee member who is willing to work on the idea. Proposals at this stage that gain enough interest are discussed in the TC39 meeting. If the discussion goes well, the proposal is moved to the next stage.

Proposals at this stage are discussed and developed by the community (including non-committee members), and if the proposal still has enough interest and is thought to have potential benefit if added to the specification, initial specification language and API are developed and discussed in the TC39 meeting. Provided everything goes well, the proposal is moved to the next stage.

At this stage, the API, syntax, and so on are refined and described in greater detail using the formal specification language. Polyfills and Babel plugins may be developed at this stage for real-world experimentation with the solution of the proposal.

Once the proposal has been described in enough detail, it can be considered for the next stage.

Proposals at this stage are almost ready to be included in the ECMAScript specification.

For proposals to be moved to the final stage, they need to meet the following two criteria:

Once the conditions mentioned above are met, and the committee has a consensus that the proposal is ready to be part of the ECMAScript specification, it is moved to the next stage.

At this stage, the proposal is complete and is ready to be included in the ECMAScript specification and ultimately be added to the JavaScript language.

A pull request is generated to the ecma262 GitHub repository to include it in the specification. Once the pull request is approved, the proposal is part of the specification and ready to be implemented in the JavaScript engines that still need to implement it.

For further details of this process, refer to a 

 on TC39's website, which explains the various stages through which proposals pass through.

---
title: How is it evolved?
description: Overview of how JavaScript is evolved as a programming language
isPublicLesson: false
---

## Ecma International, TC39

JavaScript is standardized as **ECMAScript** by **Ecma International**, a standards organization.

Within Ecma International, people responsible for developing the JavaScript language are part of the **Technical Committee 39** (TC39). This committee consists of different stakeholders from the JavaScript community. Mostly people from big companies like Google, Microsoft, etc. are part of this group.

Other people can become part of TC39 as well and make their contribution in the development of the JavaScript language. Details of how anyone can either contribute or be part of TC39 meetings as a member can be found on the [TC39 website](https://tc39.es/).

TC39 also has a [GitHub account](https://github.com/tc39) which hosts multiple repositories related to their work. Repositories include notes from TC39 meetings, different proposals for the JavaScript language, details of how TC39 works, etc.

## Proposals process

TC39 has a well-defined process through which proposals are passed before they can be added to the ECMAScript specification and ultimately be part of the JavaScript language.

Each proposal is passed through five stages which are mentioned below:

![process stages](https://d2uusema5elisf.cloudfront.net/courses/advanced-javascript-unleashed/module_01/lesson_01.04/public/assets/proposal-stages.png)

### Stage 0

The first stage represents someone's idea that they think is worthy of being part of the JavaScript language.

Not all proposals at this stage move to the next stage, but the ones that do are the ones that gain enough interest and have a TC39 committee member who is willing to work on the idea. Proposals at this stage that gain enough interest are discussed in the TC39 meeting. If the discussion goes well, the proposal is moved to the next stage.

### Stage 1

Proposals at this stage are discussed and developed by the community (including non-committee members), and if the proposal still has enough interest and is thought to have potential benefit if added to the specification, initial specification language and API are developed and discussed in the TC39 meeting. Provided everything goes well, the proposal is moved to the next stage.

### Stage 2

At this stage, the API, syntax, and so on are refined and described in greater detail using the formal specification language. Polyfills and Babel plugins may be developed at this stage for real-world experimentation with the solution of the proposal.

Once the proposal has been described in enough detail, it can be considered for the next stage.

### Stage 3

Proposals at this stage are almost ready to be included in the ECMAScript specification.

For proposals to be moved to the final stage, they need to meet the following two criteria:

-   a suite of tests
-   two compatible implementations of the proposal that passed the tests

Once the conditions mentioned above are met, and the committee has a consensus that the proposal is ready to be part of the ECMAScript specification, it is moved to the next stage.

### Stage 4

At this stage, the proposal is complete and is ready to be included in the ECMAScript specification and ultimately be added to the JavaScript language.

A pull request is generated to the ecma262 GitHub repository to include it in the specification. Once the pull request is approved, the proposal is part of the specification and ready to be implemented in the JavaScript engines that still need to implement it.

For further details of this process, refer to a [process document](https://tc39.es/process-document/) on TC39's website, which explains the various stages through which proposals pass through.


How is it evolved?

Masterclasses

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