656: Highlights

• If you want to bring classes together into modules, then you can define them in one file, producing a compilation unit. Only one class in a compilation unit can be public, however.
• If you want to bring classes together into modules, then you can define them in one directory, declaring them to be part of the same package, with a package statement:

  package package name; 
  

• Package names consist of dot-separated components. Each component corresponds to a component of the path that leads to the directory that contains the package's compilation units; the beginning of that path is specified in the value of the CLASSPATH operating-system variable.