TypeScript：它是由微软开发和维护的开源纯面向对象编程和编译语言。它受到了 JavaScript、 Java、C# 的影响。它是 C 风格的语法，可以选择性地编译成 JavaScript，用于开发 Web 和移动应用程序。 TypeScript 的第一个版本是在 2012 年 10 月。它是 JavaScript 的类型化超集，如 CofeeScript，意味着它是具有一些附加功能的 JavaScript。
Dart：它是一种开源的、通用的、基于类的、面向对象的编程语言，由谷歌开发和维护。 Dart是 JavaScript 的类型化超集。它是一种完整的脚本语言，可编译为纯 JavaScript，用于为客户端和服务器端执行构建 JavaScript 应用程序。它受到了 C# 语言、Erlang、JavaScript 和 Smalltalk 的影响。 Dart的第一个版本是在 2013 年 11 月。它是一种完整的脚本语言，这就是为什么称为 Google 替代 JavaScript 的原因。
使用Dart 的公司有 Google、Blossom 和 Workiva 等。
Dart和 TypeScript 的区别：
|
S.NO |
TYPESCRIPT |
DART |
| 01. | It is an open-source pure object-oriented programming and compiled language. | It is an open-source, general purpose class-based, object-oriented programming language. |
| 02. | It is C-style syntax and it can optionally trans-compile into JavaScript and it used to develop web and mobile applications. | It is a typed superset of JavaScript. It is a full scripting language that compiles to plain JavaScript and used to develop JavaScript applications. |
| 03. | Typescript is developed and maintained by Microsoft. | Dart is developed and maintained by Google. |
| 04. | It is licensed under Apache License 2.0. | It is licensed under BSD (Barkley Software Distribution). |
| 05. | It is a typed superset of JavaScript like CoffeeScript means it is a JavaScript with some additional features. | Dart is a full scripting language, that’s why called Google replacement of JavaScript. |
| 06. | First release of TypeScript was in October 2012. | First release of Dart was in November 2013. |
| 07. | Moderate number of libraries available in TypeScript as compared to Dart. | More number of libraries available in Dart as compare to TypeScript. |
| 08. | It is very easy for to learn and in less time it can be learned if the person knows JavaScript very well. | It is a complete programming language which needs to be learned in detail and takes time. |
| 09. | Companies that use TypeScript are Slack, Asana, and CircleCI etc. | Companies that use Dart are Google, Blossom and Workiva etc. |