Z:gnu-www-ja-gnu-linux-faq--9c3b31-Historically, AT=26amp;T which d/en

Historically, AT&amp;T which developed Unix did not want anyone to give it credit by using &ldquo;Unix&rdquo; in the name of a similar system, not even in a system 99% copied from Unix. AT&amp;T actually threatened to sue anyone giving AT&amp;T credit in that way. This is why each of the various modified versions of Unix (all proprietary, like Unix) had a completely different name that didn't include &ldquo;Unix&rdquo;.