> Sometimes I believe that software, while great, will never be huge like writing a book that will survive for centuries. Note because it is not as great per-se, but because as a side effect it is also useful… and will be replaced when something more useful is around.
That's an interesting point and thought experiment: what piece of software currently exists that will still be widely used in a century? And what's the oldest software that's still being used currently?
> And what's the oldest software that's still being used currently?
I am very interested in this question, but much of software is proprietary and you don't have much visibility into their history.
For software in the public, trivial lower bound is GCC 1.0 in 1987. Another case I know is Community Climate System Model, in continued development since 1983.
The oldest software still used is operated by banks, government agencies, schools and businesses. A large number of them are black boxes, and very expensive, so nobody will replace them. Their hardware just gets maintained ad infinitum, and the software doesn't care how old it is, so it just keeps running.
So basically, the age of software is limited by its hardware. (It's similar with animals: if nobody bumps them off and the hardware keeps ticking, the software probably will too... fish and mammals can live for hundreds of years)
That's an interesting point and thought experiment: what piece of software currently exists that will still be widely used in a century? And what's the oldest software that's still being used currently?