WordStar and Old Software Too Good to Stop Using
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Should that matter? I don't think so . Not one bit. In fact, WordStar and DOS have a couple of advantages over more modern hardware and software: probably no Internet connection, no icons, nothing buzzing or beeping or flashing at you. In sum, the perfect environment for focusing on your writing. Judging by the success of GRRM's books, it's working!
What old software do you use? Which old technologies do you hang onto even as the rest of the world chases the newest update?
Probably for the same reason. They are straightforward, robust, free of distractions and if all you need to do is type letters and perhaps do the odd spreadsheet and other things that a small business might need to do, they may still be enough.