how to use rosserial in my package nodes?

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Hi, as the result of my searching through the net I've found that we've got lot's of ways to communicate with serial port in ROS same as "rosserial Library" and "serial.h library" and it seems these two libraries are the best too, it seems good but a bit confusing. also I feel that ros serial is newer and better for my ROS Groovy version. so I've got 2 questions: 1- which of the above libraries is simpler and better? 2- if I want to use rosserial in my projects, what kind of steps should I follow? for instance suppose that I've got a working space and a package inside and I want to use rosserial in one of my package nodes.