RabbitMQ is a message-queueing software also known as a message broker or queue manager. In simple words, it is software where queues are defined, to which applications connect in order to transfer a message or messages. Message-queueing software offers persistence, delivery acknowledgements, publisher confirms and high availability. RabbitMQ client handling many languages. Most popular as Java and .Net or less as Ruby.
Machine learning is widely and successfully used nowadays. We think that computers know, but actually, they do not know - they compute. All they do is just operating on numbers. We teach them how to know by telling them what to compute.