Traditional web app overview

A typical Web2 application splits into three layers:

Frontend

• The user interface: everything your users see and interact with.
• You usually build it with HTML, CSS, and JavaScript.
• Frameworks like React, Angular, and Vue.js are widely used to make apps more dynamic and responsive.

Backend

• The application's core logic. It handles incoming user requests, runs operations, and sends back the requested data.
• Typical choices are Node.js, Python (Django, Flask, and others), Ruby on Rails, and Java.
• It is also responsible for authentication, which protects your data and keeps it consistent.

Database

• The layer that stores your app's data and lets you read and modify it.
• Options include relational systems such as MySQL, PostgreSQL, and Oracle, as well as NoSQL systems such as MongoDB, CouchDB, and Cassandra.

Together, these layers work to give users a fast, seamless experience. The next part looks at how each of them changes once you move to Web3 and the Chromia stack.