32 bit application can be supported by a 64 bit OS but 64 bit application can not be supported by a 32 bit OS.
Example: We can not install MS-Office 2010 64 bit on Win XP 32 bit or Win 7 32 bit, but we can install MS-Office 2010 32 bit in Win 732 bit as well as Win 7 64 bit.
Note: MS-Office 2007 is only available in 32 bit.
How to know about installed 32 bit application and 64 bit applications in 64 bit Windows OS:
Example: We can not install MS-Office 2010 64 bit on Win XP 32 bit or Win 7 32 bit, but we can install MS-Office 2010 32 bit in Win 732 bit as well as Win 7 64 bit.
Note: MS-Office 2007 is only available in 32 bit.
How to know about installed 32 bit application and 64 bit applications in 64 bit Windows OS:
- Open "Task Manager" in the machine.
- Navigate to "Process" tab.
- The application against which "*32" is displayed are 32 bit applications and all other are 64 bit applications. In this way you can know that browser you are running is 32 bit or 64 bit.