I have just recently installed Autocad Architecture onto my laptop and it installed 2 shortcuts onto my desktop. One of the shortcuts is called "AutoCAD Architecture 2013 - English (US Metric)" and the other is called "AutoCAD Architecture 2013 - English (Global)".
Can anyone tell me what the difference between the two are please? When I open them they both are ifferent as there is different icons and ribbons etc setup as default.
With the 2013 release of ACA, Autodesk has chosen to change the way it distributes content. Rather than sending everyone in the world all of the available content (or a large part of it), they have set up a "Global" profile with just the basic ACA tools. Regional content would then be distributed as a separate package.
I have not seen the shipping version of ACA 2013, so I do not know exactly what is included on the "disk" (if they still make disks or other physical media available). During installation, you would indicate your location and preferred units, etc (or, perhaps, simply choose what local content you want from a list?), and the corresponding regional content (such as US Metric) should also be (downloaded and) installed.
As Dean indicated, if you are working in the United States with metric units, then you would want to start with the US Metric shortcut, so that you have a more robust set of tool palettes.