Levels and Limitations

• Software systems have many levels:

  • data, file, directory, file tree
  • routine, program, subsystem, OS

• Some things automate; others don't:

  • File attributes are easy to determine.
  • File purpose needs human annotation.

• Some things persist; others don't:

  • File names and purposes are stable.
  • Exact content of files may vary.

• Consequently, we:

  • automate whatever things we can
  • annotate persistent information
  • punt the rest...