has anyone ever been able to come up with a <200 words explanation of what bitcoin is, in simple english, without words like "blockchain" and "hash", that would make even your grandma understand what bitcoin is?
I know this is not what you are looking for...
if it is your grandma you really need to convince, you could try this:
Bitcoin is like a foreign currency you need to buy when you go to another country,
except that Bitcoin is not issued by a country, it is generated on the internet.
You can run a software to solve a difficult math problem, and you would be rewarded some Bitcoins.
Or you can sell some your things or help out someone and get paid in Bitcoins.
Some might prefer to buy Bitcoins using dollars at an exchanged, similar to how you buy Euros or Yen at the airport.
You can't buy bread and milk at your local store with Bitcoins yet, but you can order all kinds of stuff on the internet.
Its popularity is growing among many countries and it value is rising steadily.
(and I skipped all the technical stuff, cos granny wouldn't understand any "peer-to-peer ledger nonsense")