Types of Information 
   Systems
       Four groups of information 
       systems
       
         (transaction processing 
        systems),
       
         (management information 
        systems),
       
         (decision support systems), dan
       
         (artificial intelligence atau 
        expert systems).
           Rankings          Function          User                          Type
           System            Main              Main                     Decision
           Information
           Expert system     Replace           Management  Structured 
                             humans in         at all levels      and 
                             decision                             unstructured 
                             making                               decisions
           Decision  Support  Assist           Top                unstructured 
           System            management  management decisions
                             in making 
                             decisions
           Management  Providing               Manajemen          Semi-
           information       various  forms madya                 structured 
           system            of information                       decision
           Transaction       Noting       the Low                 Structured 
           processing        various  forms management            Decision
           system            of 
                             transactions
      
       Tier at the bottom shows the most 
       basic information systems, or in 
       other words, from within a company, 
       because it was used to record 
       various transactions. The 
       transactions that are in a firm, 
       agency, or organization is not a sale 
       and purchase transactions only, but 
       various forms of the events that 
       caused changes in the data.
       
       Things that can be input as a transaction 
       is a natural occurrence in the institution, 
       organization or company, shall be note 
       that would later be used as material for 
       decision making. In addition to record 
       sales and purchases, which included into 
       other transactions between moving  the 
       customer's address, employee 
       promotions, employee status changes 
       from yet to be married, depreciation 
       expense charges, and changes in the 
       price of goods.