Google's Protocol Buffers (protobuf)

Google's Protocol Buffers (protobuf) is a method developed by Google for serializing structured data, similar to [[Extensible Markup Language|XML]] or [[JavaScript Object Notation|JSON]]. It is used for data interchange between services, applications, and systems, particularly in situations where efficiency and performance are critical. Protocol Buffers offer a compact and efficient way of encoding structured data.

Protocol Buffers is a binary serialization format, which means it encodes data into a compact binary representation. This makes it more efficient in terms of size and speed of encoding/decoding than text-based formats like XML or JSON.

Protocol Buffers use a language-neutral Interface Description Language (IDL) to define the schema of the data (called message types). This schema is written in .proto files, where you specify the data structure.

The .proto files are compiled to generate code in supported languages like [[Java]], [[C++]], [[Python]], etc. This allows you to easily encode and decode structured data in a variety of programming environments.

Protocol Buffers are used for storing and exchanging all kinds of structured information, such as in communication protocols, data storage, or API interfaces, particularly in microservices architectures.

They are more efficient (both in terms of space and speed of encoding/decoding) than XML and JSON. They ensure forward and backward compatibility: the data structure can evolve over time while still supporting older versions of the message.

The .proto files are compiled into source code using the Protocol Buffers compiler (protoc). This generated code provides simple accessors for each field and automatically handles the details of reading and writing the Protocol Buffers format.

Protocol Buffers are designed to handle changes to the data schema. You can add new fields to your message formats without breaking backward compatibility with code written against the "old" format.

Because of their small size and fast processing, protobuf is particularly suitable for communication between services in a distributed system, especially where bandwidth or processing speed is a concern.