What Is a Stock?
A stock is a slice of ownership in a company: a claim on its future profits and leftover assets, with limited liability. Here is what that means in practice, with real arithmetic.
Read the explainer →Library
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58 explainers, organised by topic. Start with The Basics if you're new.
The Basics
See all 10 →How the Stock Market Works
The stock market is a network of exchanges and trading venues where shares change hands. How the NYSE, Nasdaq, and TSX work, who trades, and what happens to your order.
Read the explainer →How Stock Prices Are Set
A stock's price is set by the last trade between a buyer and a seller in the order book. How bids, asks, auctions, and news move prices, with a worked order-book example.
Read the explainer →How IPOs Work
An IPO is a company's first sale of shares to the public. How underwriters, book building, lock-ups, direct listings, and SPACs work in the US and Canada, with the arithmetic.
Read the explainer →How Dividends Work
A dividend is a cash payment from a company to its shareholders. How the declaration, ex-dividend, record, and payment dates work under T+1, why the price drops, yield, and DRIPs.
Read the explainer →Stock Splits and Buybacks
Why a stock split changes the number of shares but not the value of the company, how reverse splits work, and how share buybacks compare with dividends, with the EPS arithmetic.
Read the explainer →What Is a Stock Index?
A stock index tracks a basket of stocks with one number. How the S&P 500, Dow, Nasdaq, and S&P/TSX Composite are built, and why cap-weighted and price-weighted indexes differ.
Read the explainer →Common vs Preferred Shares
Common shares carry votes and the residual claim on profits; preferred shares trade upside for a fixed dividend and priority. Dual-class shares, rate resets, and liquidation order explained.
Read the explainer →Bull and Bear Markets
A bear market is a fall of 20% or more from a peak; a bull market is a rise of 20% or more from a low. Every S&P 500 bear since 1929, how deep it went, and how long recovery took.
Read the explainer →Stocks vs Bonds
Stocks are ownership; bonds are loans. How equity and debt differ in payments, priority, risk, and long-run returns, with US data from 1928 to 2025 and why most portfolios hold both.
Read the explainer →Investing
See all 8 →How Index Funds Work
How an index fund copies a stock index, why it rarely needs to trade, what tracking error means, and why index funds cost so little to run.
Read the explainer →ETFs vs Mutual Funds: How They Differ
How ETFs and mutual funds are bought, priced and taxed, how ETF creation and redemption works, and what MERs and trailing commissions mean in Canada.
Read the explainer →How Compound Growth Works
The arithmetic of compounding with real numbers: why growth accelerates, the rule of 72, regular contributions, and the difference between nominal and real returns.
Read the explainer →Diversification Explained: Why One Stock Is Riskier Than Many
How diversification reduces single-stock risk, what correlation does, how many stocks it takes, what it cannot protect against, and home-country bias in the US and Canada.
Read the explainer →Dollar-Cost Averaging Explained: What the Research Says
How dollar-cost averaging works, the arithmetic behind its lower average cost, how it compares with investing a lump sum, and the honest trade-offs.
Read the explainer →Active vs Passive Investing: What the SPIVA Scorecards Show
How active and passive funds differ, what S&P's SPIVA scorecards for the US and Canada found through 2025, why costs and survivorship bias matter, and the limits of the evidence.
Read the explainer →Dividend Investing Explained: Yield, Total Return and Yield Traps
How dividend investing works, why yield is not the same as return, how to read a payout ratio, how yield traps happen, and how dividends are taxed in the US and Canada.
Read the explainer →How Investment Fees Work: Expense Ratios, MERs, Trailers and the Cost of 1%
The fees you pay to invest in the US and Canada, how they are charged, what changed for Canadian trailing commissions, and what 1% a year costs over 30 years.
Read the explainer →Trading & Brokers
See all 9 →How to Buy a Stock: Accounts, Orders, and What Happens After You Click Buy
A step-by-step explanation of buying your first share: choosing an account, funding it, placing an order, fractional shares, and the protections and costs to know about.
Read the explainer →Stock Order Types: Market, Limit, Stop, Stop-Limit, and Trailing Stop Orders
What each stock order type actually instructs your broker to do, with worked examples, time-in-force options, and the ways each one can go wrong.
Read the explainer →The Bid-Ask Spread Explained: The Trading Cost Nobody Bills You For
What the bid and ask are, how the national best bid and offer works, why some stocks have wide spreads, and how to calculate what crossing the spread costs you.
Read the explainer →How Stock Brokers Make Money, Including on "Commission-Free" Trades
Payment for order flow, interest on your cash, margin loans, securities lending, commissions, and currency fees: how brokers earn revenue in the US and Canada, with the rules that apply.
Read the explainer →How Short Selling Works: Borrowing, Fees, Unlimited Losses, and Squeezes
How short sellers borrow and sell shares they don't own, what the locate and margin rules require in the US and Canada, the arithmetic of borrow fees and losses, and how short squeezes happen.
Read the explainer →Margin Trading Explained: Reg T, Maintenance Margin, Margin Calls, and CIRO Rules
How buying stocks with borrowed money works in the US and Canada, with real arithmetic for leverage, interest, margin calls, and forced selling.
Read the explainer →How Stock Options Work: Calls, Puts, Premiums, and Why Most Beginners Lose
An introductory explanation of call and put options on stocks: strike, premium, expiry, and contract size, with payoff arithmetic and the research on how retail options traders fare.
Read the explainer →Stock Market Hours, Pre-Market, After-Hours, and the Move to 23-Hour Trading
When US and Canadian stock markets are open, how pre-market and after-hours sessions work, their risks, and the state of overnight and 23-hour trading as of November 2026.
Read the explainer →How a Stock Trade Settles: T+1, Clearing Houses, and Settled Cash in the US and Canada
What happens between clicking buy and owning the shares: T+1 settlement in the US and Canada since May 2024, DTCC, NSCC and CDS, settled cash, and cash-account violations.
Read the explainer →Analysis
See all 8 →How to Read an Income Statement
A line-by-line walk from revenue to net income using Apple's fiscal 2025 10-K, with the margin arithmetic and the traps that make a profit figure misleading.
Read the explainer →How to Read a Balance Sheet
Assets, liabilities and shareholders' equity explained with Apple's September 2025 balance sheet, plus book value, current ratio and debt ratios worked out step by step.
Read the explainer →How to Read a Cash Flow Statement
Operating, investing and financing cash flows explained, why profit is not cash, and how to calculate free cash flow, using Apple's fiscal 2025 10-K.
Read the explainer →Price-to-Earnings Ratio Explained: Trailing, Forward and CAPE
What the P/E ratio measures, how trailing and forward P/E differ, why P/Es vary by sector, and what Robert Shiller's CAPE data does and does not tell you.
Read the explainer →How Earnings Reports Work: 8-K, 10-Q, EPS vs Consensus and Guidance
What happens on earnings day: the press release, the 8-K and 10-Q, EPS versus analyst consensus, guidance, GAAP versus adjusted figures, and the earnings call.
Read the explainer →How to Value a Stock: Multiples, DCF and Why Every Answer Is a Range
The two main ways to value a stock, valuation multiples and discounted cash flow, with a fully worked DCF, a sensitivity table, and why small assumptions move the answer.
Read the explainer →Technical Analysis Explained Honestly: Charts, Indicators and the Evidence
What technical analysis is, how support, resistance and moving averages work, and what decades of peer-reviewed research say about whether chart-based trading pays.
Read the explainer →How to Read a 10-K (and a Canadian Annual Report on SEDAR+)
Where to find a company's annual report on SEC EDGAR or SEDAR+, what each part of a 10-K contains, and the sections worth reading first: risk factors, MD&A and the notes.
Read the explainer →Risk
See all 5 →Stock Market Risks Explained Honestly
The real risks of owning stocks: market falls, single-stock and concentration risk, inflation, sequence of returns, liquidity, and currency risk for Canadians holding US shares.
Read the explainer →Stock Market Crashes in History: 1929, 1987, 2000, 2008, and 2020
The five crashes every investor should know: how far the market fell, how long recovery took, what caused each one, and what changed afterwards.
Read the explainer →Common Stock Market Scams and How to Spot Them
How pump and dumps, social-media stock tips, fake advisers, Ponzi schemes, and impersonation scams work, with the warning signs SEC and CSA regulators flag.
Read the explainer →Investor Behaviour Mistakes: What the Research Actually Shows
Loss aversion, the disposition effect, overtrading, recency bias, and chasing performance, with the peer-reviewed evidence and an honest look at the 'behaviour gap' numbers.
Read the explainer →What Happened With GameStop in January 2021?
The GameStop short squeeze explained: the run-up, short interest above 100%, why Robinhood restricted buying, clearinghouse margin calls, and what the SEC staff report found.
Read the explainer →Accounts & Taxes
See all 6 →How Stocks Are Taxed in the US: A Plain-English Guide
How the IRS taxes stocks: short vs long-term capital gains, 2026 brackets, qualified dividends, the 3.8% NIIT, cost basis, and Form 1099-B, with worked examples.
Read the explainer →How Stocks Are Taxed in Canada: A Plain-English Guide
How the CRA taxes stocks: the 50% capital gains inclusion rate, adjusted cost base averaging, the dividend tax credit, Schedule 3, and US withholding on US shares.
Read the explainer →US Retirement Accounts Explained: 401(k), IRA, Roth, and HSA
How 401(k)s, traditional and Roth IRAs, and HSAs work: 2026 contribution and income limits, catch-ups including the age 60-63 rule, Roth catch-up, and early withdrawals.
Read the explainer →Canadian Registered Accounts Explained: TFSA, RRSP, FHSA, and RESP
How TFSAs, RRSPs, FHSAs, and RESPs work in Canada: 2026 limits, how contribution room builds, withdrawals, and why US dividends are taxed in a TFSA but not an RRSP.
Read the explainer →How Stock Markets Are Regulated in the US and Canada: SEC, FINRA, CSA, CIRO, SIPC, and CIPF
Who regulates stocks in the US and Canada, what each regulator does, and what SIPC and CIPF actually cover if your broker fails, with coverage limits as of November 2026.
Read the explainer →Wash Sale and Superficial Loss Rules: US and Canada Explained
How the US wash sale rule and Canada's superficial loss rule stop you claiming a loss when you buy back the same stock within 30 days, with worked examples.
Read the explainer →Glossary
See all 12 →What Is a Blue-Chip Stock?
A blue-chip stock is a share in a large, long-established, financially strong company. Where the term comes from, what it does and doesn't mean, and why blue chips can still fail.
Read the explainer →What Is Beta?
Beta measures how sensitive a stock's returns are to moves in the overall market. How to read a beta of 0.5, 1 or 1.5, how it's calculated, and what beta leaves out.
Read the explainer →What Is Earnings Per Share (EPS)?
Earnings per share is a company's profit divided by its shares. How basic and diluted EPS are calculated, GAAP vs adjusted EPS, and what EPS can hide.
Read the explainer →What Is Dividend Yield?
Dividend yield is a stock's annual dividends divided by its share price. How to calculate it, trailing vs forward yield, and why a high yield can be a warning sign.
Read the explainer →What Is an ETF?
An ETF (exchange-traded fund) is a fund that holds a basket of investments and trades on a stock exchange like a share. How ETFs work, where they started, and what to check before buying one.
Read the explainer →What Is Liquidity?
Liquidity is how easily you can buy or sell a stock quickly without moving its price. How to judge it from volume, spreads and depth, with a worked example of what thin liquidity costs.
Read the explainer →What Is Market Cap?
Market cap is a company's share price times its shares outstanding. How it's calculated, what float-adjusted means, and what market cap does not tell you.
Read the explainer →What Is a Short Squeeze?
A short squeeze is a rapid price rise that forces short sellers to buy back shares, pushing the price higher still. How squeezes start, a worked example, and what GameStop showed.
Read the explainer →What Is an Expense Ratio?
An expense ratio is the yearly cost of owning a fund, shown as a percentage of your investment. How it's charged, MERs in Canada, and what a 1% fee costs over 30 years.
Read the explainer →What Is the S&P 500?
The S&P 500 is a stock index of 500 leading US companies, weighted by float-adjusted market cap. How companies get in, how the weighting works, and what the index does not cover.
Read the explainer →What Is a Ticker Symbol?
A ticker symbol is the short code that identifies a listed security on an exchange. How tickers are formatted in the US and Canada, and why you should check one before you trade.
Read the explainer →What Is Volatility?
Volatility measures how much and how quickly a stock or index price swings. How it's calculated, historical vs implied volatility, the VIX, and why volatility is not the same as risk.
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