Let us keep it as understandable as possible. Inflation is the increase in value of your money in the future while deflation is the decrease in value of your money in the future. That is it. Say for example in inflation, if you have $1 now, you can buy 10 sodas. But immediately two years after, if you have $1, you can only buy 5 sodas with it. In deflation, if you have $1 now, you can buy 10 sodas. But immediately two years after, if you have $1, you can buy 20 sodas with it. Simply put, the value of your money today and in the coming years depends on how well the economy worldwide is doing.
Very well said...the book when money dies does a fantastic job in showcasing a real life scenario in Weimar Germany on Hyperinflation etc etc