Deliver a message from point A to point B as fast as possible. This is a requirement for humankind for a long time ago. History says there are records from 900 B.C. about Royal Post system in China to practice communication by written documents carried by an intermediary from one person or place to another. As you can imagine, since then, the way to deliver a message has been changed a lot not only the envelope but also the means of transmission.
Nowadays, in the era of communication between machines, there is still the need of delivering messages, and as fast as possible too. In some cases, you need speed, other cases you prefer to be sure about the reception of the message delivered besides the speed, and you may have many other needs. The systems to deliver messages were called just queue systems, just a couple of decades ago, but today they are frequently called message brokers.
There are several message brokers in the market in the current time. In this post, you will read about NATS. Engage!