In my experience Office 07 updates and replaces the earlier versions. However as 07 is backwards compatible there is no reason to have two separate versions.
Agree with Richard. However for ease of use when you send to other pcs that run the older system, when you save a document in the new version (file, save as) just below the title of the document you get a drop down box that allows you to save as a version from older versions of the program
Actually the reason why I asked was that I am thinking of doing a training course on Excel 2007 but i have Microsoft Office 2010 on my system. So far there are no courses developed on 2010 as yet, which is why I would like to do 2007. So i was intending to install 2007 keeping 2010, if you know what I mean :)
2007 is widely used in business as opposed to 2010.
Different versions can be installed on the same computer. The choice to upgrade or run side by side can be made during the installation of the later version.
However each time a different version is started the computer spends a substantial time reregistering the program. With Word and Excel a registry setting can be changed to avoid this step.
However with Access the reregistration time is very long and cannot be avoided.