Systems Analysis and Design Tutorial
It is often difficult to determine where one application system ends and the next application system begins. The reason for this is systems are often integrated to some degree with other application systems.
It is not uncommon for different application systems to share some application system components. These common components can include visual objects (e.g. graphic, behaviors) computer programs and/or databases.
For example, a single financial application might include purchasing, payroll, accounts payable, account receivables and general ledger functionality.