init() functions get called before main functions.
All variables in Go are initialized to their zero value. Pointer's zero value is nil.
Once the main function returns, the program terminates. Any goroutines that were launched and are still running at this time will also be terminated by the Go run-time.
When you write concurrent programs, it’s best to cleanly terminate any goroutines that were launched prior to letting the main function return.
Chapter 3 - packages
The convention for naming your package is to use the name of the directory containing it.