Defining Your First Protobuf Message

What is Protocol Buffers?

Protocol Buffers (Protobuf) is Google's language-neutral, platform-neutral extensible mechanism for serializing structured data — think XML/JSON, but **smaller, faster, and simpler**.

Key Rules of Proto3 Syntax

1. Every file must start with syntax = "proto3";. 2. Data structures are defined using the message keyword. 3. Every field has a **type**, a **name**, and a unique **field number tag** (e.g. = 1;). 4. Field numbers **1 through 15** take 1 byte to encode, so use them for frequently populated fields!

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Your Challenge:

Create a UserProfile message for a user management service with the following fields: - id of type string with tag 1 - username of type string with tag 2 - email of type string with tag 3 - age of type int32 with tag 4