Short answers, pulled from the story.
Phillip Cagan defined hyperinflation in 1956 as a condition starting when the monthly inflation rate exceeds 50 percent. This definition requires the rate to drop below 50 percent and stay there for at least one year to end the episode.
Peter Bernholz analyzed twenty-nine episodes following Cagan's definition and concluded that at least twenty-five were caused by printing money to cover government spending gaps. A necessary condition for these events is the use of paper money instead of gold or silver coins.
By late 1923, one US dollar was worth four trillion two hundred billion German marks. Prices doubled every two days during this period before the currency reform on the 20th of November 1923.
In mid-1946, the highest banknote value reached one hundred quintillion pengő. On the 18th of August 1946, four hundred octillion pengő became one forint.
Zimbabwe abandoned the dollar on the 12th of April 2009 in favor of using only foreign currencies. The Reserve Bank of Zimbabwe printed notes with higher face values throughout 2008 including Z$100 trillion banknotes before this decision.