I don't have a problem with this kind of question, even though there are lots of places to look it up. In my mind, this forum is to help with explanations, and the practice of giving an explanation is also useful.
However, since this is question for the Level I material, please post it and others like it in the Level I forum, rather than the General Discussion forum.
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As for the substance of the question: I've seen people get confused on this point because nominal interest rates are typically high during inflationary periods, and so they can mistakenly think that high interest rates cause inflation. In fact, in inflationary times, central banks usually try to raise real interest rates so that consumption becomes more expensive and savings more attractive. This tends to reign in immediate demand for goods and prices start to go down, or at least stop rising as fast.
Also, nominal interest rates are essentially real interest rates + the inflation rate, so nominal interest rates (which are typically the rates we observe) tend to go up when inflation increases, without affecting the future inflation rate much. This can make it seem that interest rates go up and down together, and disguise the fact that raising the *real* interest rate is a tool for fighting inflation.
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In terms of hyperinflation, the usual causes are either economic collapse, or government insolvency leading to running printing presses to pay debts. In Weimar Germany, war reparations to France depleted the German industrial base and left little for reinvestment. As a result, production declined dramatically, while the money supply stayed the same. Result: it took more money to buy the same amount of stuff. When the government faced pressure to pay more to its civil servants, veterans, and contractors to compensate for rising prices, it led to a spiral of new money chasing old prices with virtually no change in the quantity of goods, leading to hyperinflation.
In Latin America, high government borrowing and massive spending for import susbtitution industrialization in the 1960s and 70s led to hyperinflation when governments had to use hard currency and hard assets to pay external debts and had to print money to manage their internal debts. That led to inflation, which became hyperinflation as the technique continued to be used to manage debts.
Over time, a complex indexing system arose in some countries like Brazil where high levels of inflation became halfway managable for the politically important class and a way of life for nearly two decades. For example, you would buy a package of cigarettes marked as "F," and then paid whatever price was in column F of a chart when it was your turn at the cash register; salaries were indexed to the inflation rate, etc.. This meant there was a psychological component to inflation where virtually everyone was setting prices on the expectation of inflation, which became almost impossible to eliminate, through traditional monetary policy tools.
In 1994, Brazil had a clever idea in the Plano Real, which was to get people used to stable prices by introducing a unit of price which was relatively stable and indexed approximately to the dollar. This would be used along side the normal inflating price that was actually paid by consumers. Prices were quoted in "Real Units of Value," and then converted to the local currency at the daily published conversion rate once you got to the cash register. Then, once everyone was used to the idea that the stable unit measure didn't change much, the government changed the currency (with some warning) so that the new Real would be equivalent to one "Real Unit of Value," and prices would hopefully remain stable. Interestingly, the plan worked pretty well, although within a few months banks that were making money off of managing overnight nominal spreads went belly-up because the spreads collapsed from a few percent to a few basis points; also families who had gotten used to indexed salaries found that their intuitions on what were managable levels of expenses were no longer accurate.
So that's my experience (some theoretical, some first-hand) with hyperinflation.