JavaScript is a prototype-based scripting language that is dynamic, weakly typed and has first-class functions. It is a multi-paradigm language, supporting object-oriented, imperative, and functional programming styles. wikipedia.org

"TypeScript is a free and open source programming language developed and maintained by Microsoft. It is a strict superset of JavaScript, and adds optional static typing and class-based object-oriented programming to the language. Anders Hejlsberg, lead architect of C# and creator of Delphi and Turbo Pascal, has worked on the development of TypeScript." wikipedia.org

The front end is responsible for collecting input in various forms from the user and processing it to conform to a specification the back end can use. The front end is an interface between the user and the back end. wikipedia.org

Cascading Style Sheets (CSS) is a style sheet language used to describe the presentation (that is, the look and formatting) of a document written in a markup language. wikipedia.org

React is an open-source JavaScript library for creating user interfaces that aims to address challenges encountered in developing single-page applications. wikipedia.org

HyperText Markup Language (HTML) is the main markup language for web pages. HTML elements are the basic building-blocks of webpages. wikipedia.org

Web development is a broad term for the work involved in developing a web site for the Internet (World Wide Web) or an intranet (a private network).

Is a platform for web and mobile application. wikipedia.org