HTML (HyperText Markup Language) is used in this Webapp to create and structure the content of web pages. It provides the foundation for building websites by defining the layout, text, images, media, and links on a web page. HTML uses tags to mark up elements, indicating their purpose and how they should be displayed on the browser. With HTML, developers can create a wide range of web content, from simple static websites to complex web applications. Its versatility and ease of use make it an essential language for anyone interested in web development and design.

CSS (Cascading Style Sheets) is a fundamental web technology used to control the presentation and layout of HTML documents. It works alongside HTML to define how web pages should appear on different devices and screen sizes. CSS enables web developers to separate the content of a web page from its visual design, making it easier to maintain and modify the appearance of a website. CSS operates on a "cascading" principle, where multiple styles can be applied to an element, and they will be applied in a specific order of precedence. This allows for flexibility and fine-tuning of the design.

JavaScript is a versatile and popular programming language used for creating dynamic and interactive content on websites. Developed by Brendan Eich in 1995, JavaScript was originally designed to add simple interactivity to static HTML pages. However, over the years, it has evolved into a powerful and full-fledged programming language capable of building complex web applications.

An API, or application programming interface, is a set of defined rules that enable different applications to communicate with each other. It acts as an intermediary layer that processes data transfers between systems, letting companies open their application data and functionality to external third-party developers, business partners, and internal departments within their companies. The definitions and protocols within an API help businesses connect the many different applications they use in day-to-day operations, which saves employees time and breaks down silos that hinder collaboration and innovation. For developers, API documentation provides the interface for communication between applications, simplifying application integration.