Question

are debt certificates that are purchased by an investor.

Answer 1

Those are generally called bonds or more broadly “debt securities.”

Short definition
- A bond (debt security) is a certificate that represents a loan an investor makes to an issuer (government, municipality, corporation, or bank). The issuer promises to pay interest (coupon) and to return the principal (face value) at a specified maturity date.

Key features
- Face value (par): the amount repaid at maturity.
- Coupon: periodic interest payments (fixed or variable).
- Maturity: when principal is repaid (short-, medium-, long-term).
- Yield: the investor’s effective return (depends on coupon and purchase price).
- Credit rating: issuer’s creditworthiness (affects yield and risk).

Common types
- Government bonds (Treasuries), municipal bonds, corporate bonds.
- Treasury bills/notes/bonds (different maturities), zero-coupon bonds, callable/convertible bonds.
- Certificates of deposit (CDs) are bank-issued time deposits — also a form of debt but different protections and features.

What the investor gets and risks
- Income from interest and return of principal at maturity; can sell on secondary market before maturity.
- Main risks: interest-rate risk (price falls if rates rise), credit/default risk, inflation risk, reinvestment risk, and liquidity risk.

If you meant a specific instrument (e.g., certificate of deposit vs. corporate bond) or want examples, tax implications, or how to buy them, tell me which and I’ll expand.