Nominal return

An investment's return in raw currency terms, before adjusting for inflation.

Example

A statement that reads '+8% this year' is quoting the nominal return.

Nominal returns are what get advertised - always ask what the real return was before comparing two investments or two time periods.

Real return — An investment's return after subtracting inflation - what you actually gained in purchasing power.
Inflation — The general rise in prices over time, which reduces how much a given amount of money can buy.

Interest, and a rate somebody else can change — The whole return is a rate applied to a balance. What makes it unlike every other asset class is that the rate is set by the institution, can be changed at will, and you have agreed to that in advance. (10 min)
The nominal safety that loses money anyway — The balance cannot fall, and that is exactly why the real risk in this class is invisible. Inflation reduces what the money buys, and the tax is levied on the nominal interest rather than on what you actually gained. (13 min)
Inflation and real returns — A return that beats zero isn't automatically a good one. It has to beat inflation first, or your money is quietly shrinking while the balance grows. (9 min)