A web application is a software program that runs in a web browser. It can be accessed over the Internet from any device with an Internet connection, without the need for additional software or hardware installation. Web applications are used to provide online services or content such as shopping carts, email, document management and more. They are designed to work across multiple platforms, including desktop computers, tablets and mobile devices.
Web applications are built using several web development technologies, including HTML (Hypertext Markup Language), CSS (Cascading Style Sheets), and JavaScript (JS). HTML is used to structure the content on the page, while CSS helps to style it with colours, fonts, etc. JavaScript helps make pages interactive by allowing users to interact with elements on the page such as buttons, forms, etc., allowing them to submit data or trigger events such as animations, pop-ups, etc.
A typical example of a web application would be an e-commerce store where customers can browse products, add them to their shopping cart and securely checkout using their credit card information processed through an integrated payment gateway solution such as PayPal or Stripe. Other examples of common web applications include customer relationship management (CRM) systems, invoicing systems, online event registration systems, etc.
The advantage of developing a web application rather than traditional desktop software is that it can be accessed from anywhere in the world, provided there's an internet connection, making it much more convenient for users who want access to their data whenever they need it, without having to install additional programs on their computer each time they want to use it.