What are the methods of connecting a client application to a server over a network?

There are several main methods of connecting a client application to a server over a network:

1. HTTP/HTTPS requests — the most common method, used for REST API. The client sends requests (GET, POST, PUT, DELETE) and receives responses from the server.

2. WebSocket — a protocol for bidirectional real-time communication. It allows the server and client to exchange messages without re-establishing the connection.

3. TCP/UDP sockets — low-level connection methods where the client and server exchange bytes directly. TCP provides reliability, UDP offers speed.

4. gRPC — a modern framework for remote procedure calls using HTTP/2, supporting streaming and efficient serialization.

5. MQTT — a protocol for message exchange in IoT, based on publish/subscribe pattern.

In Android, HTTP/HTTPS is most often used via libraries like Retrofit, OkHttp, and for real-time communication — WebSocket.