Serialization is the process of converting data structures into a format that can be transmitted over networks or stored on disk. Examples: JSON, XML, Protocol Buffers, MessagePack, Avro. Compliance means ensuring that serialization is safe, correct, and compatible across versions and platforms. Key compliance concerns: type safety (is the deserialized data the right type?), version compatibility (can old code read new data?), security (can deserialization execute arbitrary code?), and performance (how fast is serialization/deserialization?). Proper serialization is often invisible when it works, but critical when it breaks.