Could you explain what gRPC is and how it works?

gRPC is a modern framework for remote procedure calls (RPC), developed by Google. It allows clients to invoke methods on a server as if they were local.

Main features of gRPC:

• Uses Protocol Buffers (protobuf) for describing services and serializing data — a compact and fast format.
• Supports several types of interaction: unary (one request — one response), server streaming, client streaming, and bidirectional streaming.
• Operates over HTTP/2, which provides request multiplexing, header compression, and low latency.

Example of operation:

1. A service and methods are defined in a .proto file.
2. Using the protobuf compiler, client and server code are generated.
3. The server implements the service methods.
4. The client calls methods, and gRPC handles message transmission and connection management.

This is convenient for microservice architecture, where performance and strict typing are important.