What the yield curve is actually measuring

A yield curve simply plots the interest rate on government bonds against how long until each one matures — a 3-month bond, a 2-year bond, a 10-year bond, and so on. Normally, longer-term bonds pay a higher rate, because lending money for longer carries more uncertainty and ties it up longer.

An "inverted" curve is when that relationship flips — short-term bonds pay more than long-term ones. It gets attention because it usually means investors expect interest rates, and often economic growth, to be lower in the future than they are now, which is why it's historically preceded most recessions.

The curve isn't a single fixed thing — different pairs of maturities (3-month vs. 10-year, 2-year vs. 10-year) can invert at different times and are watched by different analysts, which is part of why coverage of "the" yield curve can seem to say contradictory things at once.