You can look for OnceAndOnlyOnce and you will see it appear in many pages.
So why is this statement so powerfull? Cause of its '''redundancy'''.

In real life you see also a lot of redundancy; e.g. DNA/RNA is encoded in a very redundant way and just cause its redundancy it's stable  makes life possible.

Also a lot of information in the internet is there in a rudundant way.

Even the same page will be stored in many many places(in cache)
, again and again. 

Thanks to redundancy errors can be repaired.

Now the real question:

What way can you make use of redundancy in programming code itself?
What way can you make selfrepair happen? (e.g. you have a file mutulated file, what way can you nmake it repair itself)

I do not know the answers, but I just want to drop the question.

''Search google for "error correction".  There are many different error correction schemes.''