Securities come in four broad families: equity (ownership stakes in a company), debt (loans you make to a company or government), investment funds (pooled vehicles that hold a mix of assets), and derivatives (contracts whose value tracks something else). A fifth category, asset-backed securities, sits between debt and funds. The main types of securities differ in what you actually own, how you get paid, where you stand if the issuer fails, and how the IRS treats your returns.
What Counts as a Security
The Securities Act of 1933 lists dozens of instruments that qualify as securities, including stocks, bonds, debentures, investment contracts, and options, plus a catchall for “any interest or instrument commonly known as a security.”1govinfo. Securities Act of 1933 The working test comes from a 1946 Supreme Court case, SEC v. W.J. Howey Co., which held that an “investment contract” exists when someone invests money in a common enterprise and expects profits primarily from the efforts of others.2Justia Supreme Court Center. SEC v. Howey Co., 328 US 293 (1946) The label on the product doesn’t control. A citrus grove deal, a cryptocurrency token, or a fractional interest in a racehorse can all be securities if the economic reality fits.3U.S. Securities and Exchange Commission. Framework for Investment Contract Analysis of Digital Assets
Once something qualifies as a security, the issuer generally has to register the offering with the SEC and provide detailed disclosures, unless an exemption applies. That’s the practical protection: audited financials, risk disclosures, and ongoing reporting. If someone offers you an investment that hasn’t been registered and doesn’t fit a recognized exemption, treat it as a serious warning sign.
Equity Securities
Equity securities are ownership stakes. When you buy shares, you become a partial owner with a claim on the company’s earnings and remaining assets. The two main forms are common stock and preferred stock, and they behave quite differently despite both being called equity.
Common Stock
Common stock is what most people mean when they say “stocks.” Each share carries a vote on major corporate decisions, like electing the board. Your return comes primarily from price appreciation, though many companies pay dividends out of profits. Those dividends are discretionary; the company can cut or skip them at any time.
The tradeoff for that upside potential is that common stockholders sit last in line if the company fails. Bondholders get paid first, then preferred stockholders, and whatever remains goes to common shareholders. In most bankruptcies, that remainder is nothing.
Preferred Stock
Preferred stock sits between common stock and bonds. Preferred shareholders typically receive a fixed dividend that must be paid before any dividend reaches common stockholders, and they have priority over common shareholders in a liquidation once creditors are satisfied. In exchange, preferred shareholders usually don’t vote on corporate matters.
The fixed dividend makes preferred stock behave a lot like a bond. When interest rates rise, preferred share prices tend to fall. Some preferred shares are convertible, meaning you can exchange them for a set number of common shares if the company performs well. Others are callable, meaning the company can buy them back at a predetermined price after a certain date.
Debt Securities
Debt securities flip the relationship. Instead of owning part of the company, you’re lending it money. The issuer owes you regular interest payments and has to return your principal on a set date. That obligation is legally binding, and missing a payment can push the issuer into default.
Corporate Bonds
A corporate bond is an IOU from a company. You lend a specified amount (the face value), collect periodic interest payments (the coupon), and get your principal back at maturity. The SEC classifies maturities as short-term (under three years), medium-term (four to ten years), or long-term (over ten years).4U.S. Securities and Exchange Commission. Investor Bulletin: What Are Corporate Bonds?
Because interest payments must be made before any dividends reach shareholders, bonds are generally safer than stock from the same company. That safety comes with lower expected returns. Credit ratings are the key indicator of how likely the issuer is to make good on payments. Investment-grade bonds carry lower yields because default risk is small; high-yield or “junk” bonds pay more because the risk is real.
Municipal Bonds
Municipal bonds are issued by state and local governments to fund public projects like roads, schools, and water systems. The main draw is tax treatment: interest on most municipal bonds is exempt from federal income tax.5Internal Revenue Service. Module B – Introduction to Federal Taxation of Municipal Bonds If you buy bonds issued in your own state, the interest may also be exempt from state and local tax, depending on where you live. That advantage makes municipal bonds particularly useful for investors in high tax brackets: a 3% municipal yield can deliver more after-tax income than a 4% corporate yield, depending on your marginal rate.
Risk varies within the category. General obligation bonds are backed by the taxing authority of the issuing government. Revenue bonds depend on income from a specific project, like a toll road or hospital, and default risk tracks the project’s performance.
Commercial Paper
Commercial paper is short-term unsecured debt that large corporations use for quick funding needs like payroll or inventory.6Federal Reserve. Commercial Paper Rates and Outstanding Summary Maturities range up to 270 days but average around 30 days. Only companies with strong credit ratings can issue it at reasonable rates. Retail investors rarely buy commercial paper directly, but if you own a money market fund, you probably hold some indirectly.
Investment Funds
Most individual investors don’t buy stocks and bonds one at a time. They use pooled vehicles that deliver a diversified slice of the market through a single purchase. These funds are themselves securities, registered with the SEC and subject to their own disclosure rules.
Mutual Funds
A mutual fund pools money from many investors and uses it to buy a portfolio of stocks, bonds, or other assets. Each share represents your proportionate ownership of that portfolio.7U.S. Securities and Exchange Commission. Mutual Funds and ETFs A professional adviser decides what to buy and sell.
Mutual funds price once per day, after the major exchanges close. Everyone placing an order that day gets the same price, called the net asset value (NAV). You buy and redeem shares through the fund itself, not on an exchange, which means no intraday trades and no limit orders. Costs include annual management fees and, in some cases, sales charges (loads) paid on purchase or sale. Those fees come out regardless of how the fund performs.
Exchange-Traded Funds
ETFs hold a basket of assets much like mutual funds, but they trade on stock exchanges throughout the day, with prices moving in real time.8U.S. Securities and Exchange Commission. Investor Bulletin: Exchange-Traded Funds (ETFs) You can place limit orders, stop-loss orders, and even short-sell an ETF, none of which is possible with a traditional mutual fund. ETFs are generally more tax-efficient than mutual funds because of how they handle redemptions internally. The tradeoff is that an ETF’s market price can drift slightly above or below the actual value of its holdings during the trading day, especially for thinly traded funds.
Money Market Funds
Money market funds are a specialized type of mutual fund that invests in very short-term debt like Treasury bills, commercial paper, and certificates of deposit.9SEC Investor.gov. Money Market Funds: Investor Bulletin Most aim to hold their share price steady at $1.00, which lets them function as a parking spot for cash. Yields are modest, risk is low, and the funds are not FDIC-insured.
Asset-Backed Securities
Asset-backed securities (ABS) are created by bundling loans or receivables and selling slices of that bundle to investors. The underlying collateral can be home mortgages, auto loans, student loans, or credit card receivables. Payments from borrowers flow through to ABS holders, minus servicer fees.10U.S. Securities and Exchange Commission. Dodd-Frank Act Rulemaking: Asset-Backed Securities
A single bundle is typically divided into tranches with different risk-return profiles. The safest tranche gets paid first and earns the lowest yield; the riskiest tranche absorbs losses first but earns the highest yield. Mortgage-backed securities (MBS) are the best-known type. Those issued or guaranteed by government-sponsored entities like Fannie Mae and Freddie Mac carry substantially less credit risk than private-label MBS, which have no government backing and depend entirely on the quality of the underlying loans. Retail investors usually encounter ABS through bond funds rather than by buying them directly.
Derivative Instruments
Derivatives don’t represent ownership of anything or a loan to anyone. They’re contracts whose value depends on the price of some other asset, whether that’s a stock, a commodity, a currency, or an interest rate. The three most common types are options, futures, and swaps.
Options
An option contract gives the buyer the right to buy or sell an underlying asset at a fixed price (the strike price) on or before a specific date. A call is the right to buy; a put is the right to sell. A single equity option contract typically covers 100 shares of stock.11SEC Investor.gov. Investor Bulletin: An Introduction to Options
The buyer pays a premium upfront and can walk away if the trade doesn’t work, losing only the premium. The seller (or writer) collects the premium but takes on the obligation to fulfill the contract if the buyer exercises. That asymmetry makes options useful for hedging: you can protect against downside without giving up all your upside. It also makes selling certain options dangerous. Writing uncovered call options carries theoretically unlimited loss potential.
Futures
A futures contract is a standardized agreement to buy or sell an asset at a set price on a set date. Unlike options, both sides are obligated to follow through. Futures trade on regulated exchanges with standardized terms for quantity, quality, and delivery date, which makes them highly liquid.
Originally developed for agricultural commodities, futures now cover everything from crude oil to stock indexes to interest rates. Most contracts settle in cash rather than physical delivery, since the typical buyer has no interest in actually receiving 5,000 bushels of corn.
Swaps
Swaps are privately negotiated contracts where two parties agree to exchange payment streams over a period of time. The most common variety is an interest rate swap, where one party trades a fixed rate for a floating rate. A company with a variable-rate loan might enter a swap to lock in a fixed rate and reduce exposure to rising rates.
Unlike futures, swaps don’t trade on exchanges. They’re customized agreements negotiated directly, often through dealers. That customization is useful for tailoring risk, but it introduces counterparty risk, since no exchange stands behind the trade.
Who Regulates Derivatives
Derivatives fall under a split regulatory framework. The Commodity Futures Trading Commission (CFTC) oversees swaps and futures. The SEC regulates security-based swaps, which are tied to individual securities or narrow indexes. Both agencies share jurisdiction over “mixed swaps” that straddle the line.12U.S. Commodity Futures Trading Commission. Fact Sheet: Final Rules and Interpretations – Further Defining Swap For investors, the takeaway is that derivatives trading requires accounts specifically authorized for those products, with margin rules and disclosures different from ordinary stock trading.
How Returns Are Taxed
Tax treatment is one of the biggest practical differences between security types. The IRS treats interest, dividends, and capital gains differently, and the type of security you hold usually determines which bucket applies.
Interest Income
Interest from corporate bonds, savings accounts, and certificates of deposit is taxed as ordinary income at your regular federal rate.13Internal Revenue Service. Topic No. 403, Interest Received For a high earner, that can mean losing close to 40% of the interest to federal tax alone. Municipal bond interest is generally exempt from federal income tax, which is why municipal bonds can be worth considering even at lower nominal yields.5Internal Revenue Service. Module B – Introduction to Federal Taxation of Municipal Bonds
Capital Gains
When you sell a security for more than you paid, the profit is a capital gain. If you held the investment for more than one year, it’s a long-term capital gain, taxed at 0%, 15%, or 20% depending on your income. For 2026, single filers with taxable income below $49,450 pay 0% on long-term gains; the 20% rate begins above $545,500 for single filers and $613,700 for joint filers. Investments held one year or less generate short-term gains, taxed at your ordinary income rate. The difference between a 15% long-term rate and a 37% ordinary rate on the same gain is large enough that holding-period planning deserves real attention.
Dividends
Dividends fall into two categories. Qualified dividends, generally from U.S. corporate stock held for at least 61 days, are taxed at the same favorable rates as long-term capital gains. Non-qualified (ordinary) dividends are taxed at your regular income rate. Dividends from real estate investment trusts (REITs) and most preferred stock dividends with short holding periods are typically non-qualified. High-income taxpayers (above $200,000 for single filers or $250,000 for joint filers) also face an additional 3.8% net investment income tax on dividends, interest, and capital gains.