Tim Bray, in his short post noting the death of Dennis Ritchie, said this:

Unix combines more obvious-in-retrospect engineering design choices than anything else I’ve seen or am likely to see in my lifetime.

Absolutely true. It’s one of the reasons—perhaps THE reason—that UNIX is still going strong over 30 years after its invention.

Bray goes on to say this:

It is impossible—absolutely impossible—to overstate the debt my profession owes to Dennis Ritchie. I’ve been living in a world he helped invent for over thirty years.

Also true. The machines I use for my work & pleasure all run some variant of UNIX, & for that I thank Ritchie & all those who followed him.

Note: If you don’t know who Dennis Ritchie was, hie thee to Wikipedia.