20 computer software, nemes of their inventor and year of invention

What?

I think you can do the research on this one. It will be easier if you stay away from the larger corporations.

Just go to download.com and type in a key word. You'll probably get hundreds of results. Just pick your twenty, the author names are on the site. There are usually links to their home page or an email where you can identify their year of origin and most any other info you need.