Apache Avro

Apache Avro is a row-oriented data serialization format. Schemas are defined in JSON and travel with the data (or by reference through a schema registry), enabling compact binary encoding without per-record field names.

Its defining strength is schema evolution: reader and writer schemas are resolved against each other under well-defined compatibility rules, so producers and consumers can upgrade independently — the property that made Avro the default encoding for Kafka-based pipelines.

Avro fits records in motion and write-heavy raw zones; columnar formats like Parquet complement it at rest for scan-heavy analytics. Protocol Buffers and JSON Schema are the usual alternatives in registry-governed streaming setups.