The documentation that you see on the site is always for the current version unless you are looking into some of the archived documentation. For version 1 products we often do not designate a version number, but for newer versions it should be listed in the documentation. So if you are working on a version 2 product you should check that your documentation is referencing this version.
The best thing to do is visit the support page for a given product and get the current getting started guide and documentation as updates can be made to this information on a regular basis.