If you find yourself wanting to work with your RDD in another language, there are a few options. With Java/Scala, you can try using the JNI, and with Python, you can use the FFI. Sometimes, however, you will want to work with a language that isn't C language or with an already compiled program. In that case, the easiest thing to do is use the pipe interface that is available in all of the three APIs. The Stream API works by taking the RDD, serializing it to strings, and piping it to the specified program. If your data happens to be plain strings, this is very convenient; but if not, you will need to serialize your data in such a way it can be understood on either side. JSON or protocol buffers can be good options depending on how structured your data is.