Bond and yield
A loan to a government or company that pays interest.
Bonds pay fixed interest and return the principal later. The yield is the return an investor earns; bond prices and yields move in opposite directions.
A bond is a loan. You hand over the principal, collect fixed interest along the way, and get the principal back at maturity. Governments and companies issue them to raise money. US government bonds, Treasuries, are treated as the benchmark for a safe return because the government is considered extremely unlikely to default.
The key thing to internalize is that price and yield move in opposite directions. If a bond pays a fixed coupon and its market price falls, a new buyer earns a higher yield on the cheaper price, and vice versa. So when you hear yields are rising, bond prices are falling. The shape of yields across maturities, the yield curve, is one of the most-watched signals in markets.