In a business environment, there is a greater need for networking, computers sharing information, and that several people may use the same computer. This brings into play a whole set of requirements, such as security, that the OS must address. Computers offer special features such as grammar check, spell check or simply the option of using graphics. Computers don't offer those options, certain software do. If you don't have the software that has it, you don't have that feature.
Computers are different in that they're designed to add new features.
To get new typewriter options you generally buy a new typewriter. The Mac is better protected from viruses because it doesn't run Outlook. There is an Outlook and Outlook expressed for the Mac, they just don't have the aspects of the Windows versions that virus creators take advantage of. Windows users can become less susceptible to viruses by using a different e-mail software such as Eudora. Upgrading allows consumers to have a stable and reliable system.