A business object is a Class that is unique to a business entity. For example lets say we have a billing system then we could write an Invoice business object (class), crude example below. Invoice ----Date ----Account ----Total ----DeliveryNote ----PickSlipReference An invoice will contain orders so we write an order business object (class) Order -----Date -----ProductCode -----Quantity -----ProductName -----UnitPrice Now we could adapt our Invoice class to contain an Orders attribute which is an array of Order business objects. An interesting thing that may help you is to read up on the principle of design by contract, Eiffel (www.eiffel.com) have some OO literature specific to this. To summarise design by contract states that each business object should be able to create contracts with each other just like the real business world, for example Invoice has a business contract with Order. Ther eis more to it but I wont babble ... Hope this helps ... Graeme Matthew Analyst Programmer Mercer Investment Consulting Level 29, 101 Collins Street, Melbourne, VIC, 3001, Australia Tel - 61 3 9245 5352 Fax - 61 3 9245 5330 visit http://www.merceric.com -----Original Message----- From: Yohanes Santoso [mailto:ysantoso / jenny-gnome.dyndns.org] Sent: Friday, 20 September 2002 9:02 To: ruby-talk / ruby-lang.org Subject: Re: Business Objects This is Off Topic, but what's a business object? Can someone describe it in plain, programmer language? TIA, YS __ ********************************************** This e-mail and any attachments may be confidential or legally privileged. If you received this message in error or are not the intended recipient, you should destroy the e-mail message and any attachments or copies, and you are prohibited from retaining, distributing, disclosing or using any information contained herein. Please inform us of the erroneous delivery by return e-mail. Thank you for your cooperation. ********************************************** ec03/04