The QB2012 - QuickBooks 2012 File was produced by a Mac edition of the money management software for QuickBooks. It would be used to store financial data of companies, information of payroll, and information of customers and employees. This file is used to keep track of business finances and generate tax forms along with making sure that payroll reports are done accurately and that the financial reports are up to date.
If you would like to integrate this software information with the Windows QuickBooks edition you will need to export files as QBB file by making sure you choose File → Back-Up to the Windows QuickBooks and then make sure you import the QBB file into the Windows form of software. To do this, you will need to choose File → Open or choose Restore Company. Something worthwhile to remember is that earlier forms of Mac QuickBooks will use the add-on QB2011 or QB2010 and so on. Since QuickBooks 2012 was released, these add-ons are now legacy.