Most of the applications you use these days follow the Client-Server Architecture. The Application itself is considered the Client or the Front-End part, and it needs to talk to a Server or the Back-End to load or pull the data. This communication is established with the help of the HTTP protocol, and yes, it’s the same protocol that powers our Web.
The Client can directly call the HTTP Services exposed on a Server by sending HTTP requests. This is where REST APIs come into the picture. REST is basically a convention for building these HTTP Web Services. A REST API like Spring Boot REST API can help you retrieve information from another system.
1. Course
This has just one class Course where multiple operations are being performed. Normal CRUD operations are there.
2. Wallet
This can be used for expense tracking. Multiple users can register and create their own category as well. Once categories are created, transactions can be created.