What is Apache Avro?

Avro facilitates the exchange of big data between programs written in any language. With the serialization service, programs can efficiently serialize data into files or into messages. The data storage is compact and efficient. Avro stores both the data definition and the data together in one message or file.

Avro stores the data definition in JSON format making it easy to read and interpret; the data itself is stored in binary format making it compact and efficient. Avro files include markers that can be used to split large data sets into subsets suitable for Apache MapReduce processing. Some data exchange services use a code generator to interpret the data definition and produce code to access the data. Avro doesn't require this step, making it ideal for scripting languages.

A key feature of Avro is robust support for data schemas that change over time — often called schema evolution. Avro handles schema changes like missing fields, added fields and changed fields; as a result, old programs can read new data and new programs can read old data. Avro includes APIs for Java, Python, Ruby, C, C++ and more. Data stored using Avro can be passed from programs written in different languages, even from a compiled language like C to a scripting language like Apache Pig.