Alan Kay was quoted several years ago to the effect that there had been only three new things in software in the preceding 20 years (effectively the lifespan of PCs). One of them was Spreadsheets.
Does anyone remember the other two?
Who is Alan Kay? (a few may ask.) His work at Xerox Parc arguably did more to shape our current software paradigm than any other influence.
No mention of spreadsheets, but how about this quote, from an interview with a 1991 issue of Byte Magazine:
Source
I will try to remember what I said, but none of the answers so far are correct (every one of them was done in the 60s and 70s before the commercialization of PCs in the 80s).
However, we could start all over and try to think of new inventions in computing since the 1980s.
Mice and GUI's
Perhaps this link leading to the paper
The Most Important Software Innovations written by David A. Wheeler
helps you remembering the two missing things.
P.S.: I personally would choose (1980 and later):
I am pretty sure C++ wasn't one of the two things.
See https://stackoverflow.com/questions/58640/great-programming-quotes#58810
When ever I think about xerox parc I always remember this quote from triumph of the nerds by steve jobs: