Publishers and Subscribers
When explaining basic ROS concepts, we discussed a few nodes used for publishing data and some others used for subscribing to that data. Knowing this, it is not hard to imagine that nodes can be classified into two groups, depending on the kind of action they perform. They can be publishers or subscribers. Why do you think it is important to distinguish between these two types of nodes?
As mentioned earlier, publishers are nodes that provide information to other nodes. They usually work with sensors to check the environment status and convert it into valuable outputs for subscribers that can receive this information.
On the other hand, subscribers usually get an understandable input and process it. They then decide which action will be launched depending on the obtained result.
As this is a rarely used type of programming, it will be interesting to follow some examples of how these nodes really work, before starting to use them with robots and simulators. So, let...
