The update of a SW product usually solves a newly appeared problem, or adds a new function. The update can contain
several functions and solutions. For Windows, there are issued update files in socalled Service Packs. The update does not change the whole number of the original version, but only the specific part of the number - usually
the number behind the decimal point. E. g. after installation of the Service Pack marked as no. 1
the number of the version will be changed from Windows XP to Windows XP SP1.