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Bonds
A bond is a loan you make to a government or a company — how the interest works, why the ride is steadier than stocks, and what can still go wrong.
When you buy a bond, you're making a loan. A government or a company borrows your money, pays you interest on a schedule, and returns the amount you lent on a set end date. You're not buying a piece of anything — you're the lender, and the borrower owes you. That one fact explains almost everything about how bonds behave.
The deal, piece by piece
The borrower is called the issuer — whoever took your money and owes it back. The interest rate the bond pays is called the coupon. The end date, when the issuer repays the loan and the payments stop, is the maturity.
Put numbers on it — round, made-up ones, just to keep the math easy. Say you lend $100 at a 5% coupon. You collect $5 a year, usually split into two payments, for as long as the bond runs. At maturity, the last payment arrives along with your $100. Notice what the deal doesn't depend on: how the borrower's year went. The payments were set when the bond was issued, and they don't change.
Why bonds ride steadier than stocks
A stock is a small piece of ownership in a company, and an owner only does well if the company does well. A bondholder is different. You're owed money either way — great year or dull year, the coupon is the same, because it's written into the contract. That's why bond prices tend to swing far less than stock prices.
The calm cuts both ways, though. If the company you lent to triples in size, your bond still pays $5 a year and $100 at the end. Lenders give up the upside, and that's a big part of why stocks have historically returned more than bonds over long periods.
What can still go wrong
Steadier isn't the same as safe, so be clear-eyed about two things.
The borrower can fail. A bond is only as good as the issuer's ability to pay, and the chance that they can't is called credit risk. A loan to the U.S. government is about the steadiest loan you can make; a loan to a company depends on that company staying healthy. If a borrower fails, bondholders can lose some or even all of what they lent. And as a rule, borrowers who are more likely to struggle have to offer a higher coupon to get the loan — a big payout is compensation for risk, not a gift.
Prices wobble when interest rates change. Suppose new bonds start paying 6% while yours pays 5%. Nobody will pay full price for yours anymore, so if you sold that day, you'd get a bit less than you paid. This is called interest-rate risk. The gentle part: if you keep the bond to maturity, you still collect every payment and the full amount back — as long as the issuer pays. The wobble mostly matters if you have to sell early.
The calm part of the mix
A portfolio is your whole collection of investments, and most long-term portfolios hold stocks and bonds together. Stocks are the growth. Bonds are the ballast: they move on different news — interest rates and one borrower's reliability, not profits — so in many years when stocks fall, bonds hold up better. Not always; both have fallen together before. But the tendency is strong enough that mixing the two has historically made the whole ride smoother than stocks alone.
| Stocks | Bonds | |
|---|---|---|
| What you are | An owner of a small piece of a company | A lender the company or government owes |
| What you're promised | Nothing | Interest on a schedule, plus the loan repaid at maturity |
| If the business booms | Your piece can grow a lot | The same payments — your upside is capped |
| If the business struggles | The price can fall far | You're still owed every payment, unless the borrower fails |
| The usual ride | Big swings | Much smaller swings |
Neither column is the winner. They do different jobs, which is exactly why a mix of the two can be steadier than either one alone.