In Bash, a function is a block of code that can be invoked by its name. A function can take arguments, which are passed to the function as positional parameters. The $1 variable refers to the first argument, $2 to the second argument, and so on. The function can access the number of arguments passed to it by using the $# variable. In this case, thefunction myfunction simply echoes the first and second arguments to the standard output. Therefore, when the command myfunction A B C is executed, the output is A B, since the third argument C is ignored by the function. References:
* [LPI Linux Essentials - Topic 103: Command Line Basics]
* [Bash Functions]