Learn Investing
Practical investing, from the ground up. 227 lessons on how markets, companies and money actually work — beginner to advanced. Trade real prices in a simulated portfolio, and every trade has to be backed by real reasoning, not a guess.
Learning on your own? Start here. No class or teacher needed — work through it at your own pace. If you are studying for an exam instead, the IB, AP and Personal Finance courses follow those syllabuses unit by unit.
Beginner Investing
55 lessonsHow to Value a Company: The Three Main Approaches
There's no single 'true' price for a company — analysts triangulate using three different methods and see where they agree.
Start Lesson Practice this topicEnterprise Value vs. Market Cap: What's the Real Price Tag?
Two companies can have identical market caps and very different real price tags once you account for debt and cash.
Start Lesson Practice this topicFree Cash Flow: Why It Matters More Than Net Income
Net income can be shaped by accounting choices — actual cash is much harder to fake.
Start Lesson Practice this topicThe Cash Flow Statement: Why Profitable Companies Can Still Run Out of Cash
Net income is an opinion, cash is a fact — this is the statement that tracks the fact.
Start Lesson Practice this topicUnderstanding Volatility and Standard Deviation in Investing
Volatility isn't automatically bad — it just means bigger swings in both directions, not only down.
Start Lesson Practice this topicPosition Sizing: How Much of Your Portfolio Should One Stock Be?
Even a great company deserves a size limit — because 'great' and 'risk-free' are never the same thing.
Start Lesson Practice this topicRebalancing: Why Selling Winners and Buying Losers Sometimes Makes Sense
Rebalancing forces a systematic 'sell high, buy low' discipline that fights your own instincts on purpose.
Start Lesson Practice this topicStablecoins Explained: How They're Supposed to Stay at $1
A stablecoin is only as reliable as what actually backs it — and not every one is backed the same way.
Start Lesson Practice this topicAlternative Assets Beyond Crypto: Gold, Collectibles, and Why They're Different from Stocks
Gold has no earnings call, no CEO, and no dividend — its entire case rests on scarcity and demand, not a business.
Start Lesson Practice this topicRevenue Recognition: Why "Revenue" Isn't Always When Cash Changes Hands
A company can collect cash today and still not be allowed to call it revenue yet — the accounting rules for when revenue actually counts.
Start Lesson Practice this topicWorking Capital and the Cash Conversion Cycle
The real mechanics behind how a genuinely profitable company can still run out of cash and go bankrupt.
Start Lesson Practice this topicAccounting Red Flags: Warning Signs Worth Investigating Further
None of these prove wrongdoing on their own — but each one is a real, well-documented pattern worth digging into before trusting the headline numbers.
Start Lesson Practice this topicEBITDA: What It Hides, and Why Some Investors Distrust It
A widely used shortcut for comparing companies — and a metric one of the most respected investors in history urged people to view with real suspicion.
Start Lesson Practice this topicHow to Actually Compare Two Companies' Financial Statements
Lining up two companies' raw numbers side by side is close to meaningless — real comparison requires normalizing for size, timing, and accounting choices first.
Start Lesson Practice this topicSeasonality: Why Comparing Q4 to Q3 Can Be Misleading
Some businesses are naturally lumpy through the year — comparing the wrong quarters to each other can make a perfectly normal pattern look like a real trend.
Start Lesson Practice this topicGross Margin: The First Number That Tells You What Kind of Business You're Looking At
One percentage, calculated in seconds, that instantly reveals more about a business's fundamental economics than almost any other single figure.
Start Lesson Practice this topicOperating Income vs. Net Income: Where They Diverge and Why It Matters
Two different "profit" numbers on the same income statement, and the gap between them often tells a more honest story than either one alone.
Start Lesson Practice this topicThe Five Sources of Economic Moats, and How to Test Whether One Is Real
A widely used research framework for where a durable competitive advantage actually comes from — plus the one number that tests whether it's real.
Start Lesson Practice this topicNetwork Effects, Deep-Dive: Direct, Indirect, and When They Reverse
The moat that gets stronger the more people use it — and the same mechanism working in reverse, which can unravel just as powerfully.
Start Lesson Practice this topicSwitching Costs: Why Enterprise Software Is So Hard to Displace
Ripping out a company's core software isn't like switching coffee brands — the real reasons enterprise switching costs run so high.
Start Lesson Practice this topicHow to Evaluate a Management Team, Beyond Just Trusting the Investor Presentation
Management quality is genuinely hard to assess from the outside — but a few concrete, checkable things go a lot further than reading a polished slide deck.
Start Lesson Practice this topicInsider Ownership and "Skin in the Game": Why It Matters for Business Quality
Not about tracking individual trades — about a deeper structural question: how much of the company do the people running it actually own?
Start Lesson Practice this topicSpotting Structural Decline Early: What Blockbuster and Kodak Have in Common
Two of the most-cited business collapses in history share an uncomfortable detail: the people inside both companies saw the threat coming.
Start Lesson Practice this topicTAM Analysis: What "Total Addressable Market" Really Means, and Its Most Common Pitfall
One of the most cited numbers in any growth pitch — and one of the easiest to inflate without anyone checking the math underneath it.
Start Lesson Practice this topicMarket Share Ceiling Analysis: How Much Bigger Can a Company Realistically Get?
Even a dominant company eventually runs into real limits on how much more market share it can capture — the honest question is where that ceiling actually sits.
Start Lesson Practice this topicCapital-Light Business Models: Why Some Companies Need Very Little Money to Grow
Two companies can grow revenue at the same rate and still be fundamentally different investments, depending on how much cash that growth actually consumes.
Start Lesson Practice this topicRecurring Revenue: Why Predictable Revenue Often Commands a Higher Valuation
A dollar of subscription revenue and a dollar of one-time sale revenue aren't treated as equal by investors — and there's real math behind why.
Start Lesson Practice this topicThe Price-to-Sales Ratio: Valuing Companies With No Profits (Yet)
When a company has no earnings, P/E can't be calculated at all — price-to-sales steps in, using the one number almost every company actually has: revenue.
Start Lesson Practice this topicPrice-to-Book Ratio: Essential for Banks, Nearly Useless for Software
The same ratio that's a core tool for valuing a bank tells you almost nothing useful about a company whose real assets never show up on its balance sheet.
Start Lesson Practice this topicEV/EBITDA: The Multiple Professionals Reach for First
When two companies run the same operating business but carry different amounts of debt, P/E tells two different stories — EV/EBITDA is built specifically to tell one consistent story.
Start Lesson Practice this topicSum-of-the-Parts Valuation: Pricing a Conglomerate Piece by Piece
A company that runs several unrelated businesses under one roof usually shouldn't get one blended multiple — value each piece on its own terms, then add them up.
Start Lesson Practice this topicComparable Company Analysis: How to Pick a Peer Set You Can Defend
"Comps" sounds simple until you actually have to pick them — the peer set you choose can swing a valuation as much as the multiple itself.
Start Lesson Practice this topicWhat the Market Is Really Pricing In
Instead of asking whether a stock looks expensive, work the valuation formula backward and find out exactly what has to be true for the current price to make sense.
Start Lesson Practice this topicWhy Two Analysts Can Value the Same Company Completely Differently
Same public filings, same company, same day — and two competent analysts can still publish price targets that differ by 50% or more. Here's exactly which assumptions cause that gap.
Start Lesson Practice this topicValuation in a Rising vs. Falling Interest Rate Environment
The same discount-rate math that values a bond explains why growth stocks get hit hardest when rates rise, and why they often rebound hardest when rates fall.
Start Lesson Practice this topicHow the 11 GICS Sectors Work, and Why Sector Matters as Much as the Company
Every public company is sorted into one of 11 standardized sectors — and knowing which one changes what "normal" even looks like for that business.
Start Lesson Practice this topicHow to Analyze a Technology Company
High margins, fast growth, and heavy R&D spending are the norm in tech — which means the questions worth asking are different from almost any other sector.
Start Lesson Practice this topicHow to Analyze a Financial Services Company, Including Banks and Insurance
Banks and insurers don't fit the normal analysis playbook at all — their balance sheets ARE the business, not just a supporting document.
Start Lesson Practice this topicHow to Analyze a Healthcare Company and Navigate Regulatory Risk
A promising drug can be worth billions — or worthless — depending entirely on a regulatory decision no amount of financial analysis alone can predict.
Start Lesson Practice this topicHow to Analyze a Consumer Company and Understand Brand Value
Consumer companies sell to people whose habits and loyalty shift constantly — brand strength is the difference between pricing power and a permanent price war.
Start Lesson Practice this topicHow to Analyze an Energy Company and Commodity Exposure
Energy companies don't set their own most important price — the commodity market does that for them, and everything else follows from there.
Start Lesson Practice this topicHow to Analyze a Real Estate Company and Understand REITs
You don't need to buy a building to invest in real estate — REITs let you own a slice of real, income-producing property through an ordinary brokerage account.
Start Lesson Practice this topicWhat Sector Rotation Is, and How Investors Use It
Different sectors tend to lead and lag at different points in the economic cycle — sector rotation is the strategy built around trying to anticipate which one's turn is next.
Start Lesson Practice this topicWhy Some Sectors Outperform in Recessions, and Others Collapse
A recession doesn't hit every sector the same way — the difference between a sector that holds steady and one that craters often comes down to a single question: can people delay buying this?
Start Lesson Practice this topicHow to Use Sector ETFs to Express a Macro View
If you have a view on where the economy is heading but not which specific company will benefit most, a sector ETF lets you act on that view directly, with a single trade.
Start Lesson Practice this topicWhat the SEC Is, and Why Public Companies Have to File With It
Every public company's most important disclosures exist because of one specific law passed after the country's worst stock market crash — not out of corporate generosity.
Start Lesson Practice this topicWhat an 8-K Is, and Why Some 8-Ks Matter More Than Others
While a 10-K covers a whole year, an 8-K exists for a single reason: something material just happened, and investors need to know within days, not months.
Start Lesson Practice this topicWhat Related Party Transactions Reveal About Potential Conflicts of Interest
When a company does business with its own CEO's family member or a board member's other company, that deal gets a special disclosure — and a special level of scrutiny.
Start Lesson Practice this topicHow to Read the Footnotes Where Companies Disclose What's Easy to Miss
The headline numbers get all the attention — but the footnotes are where accounting policy choices, contingent liabilities, and real risk details actually live.
Start Lesson Practice this topicWhat a Proxy Statement Reveals About Executive Compensation and Corporate Governance
This is the one filing where you can see, in exact dollar figures, whether a CEO's pay is actually tied to performance — or just goes up regardless.
Start Lesson Practice this topicWhat a Form 4 Is, and How to Track Insider Buying and Selling in Real Time
Every time a company insider buys or sells their own stock, they have to tell the SEC within days — and that filing is public, free, and searchable by anyone.
Start Lesson Practice this topicWhat a 13F Is, and How to See What the Biggest Funds Are Buying and Selling
Every large institutional investor has to reveal its U.S. stock holdings publicly, every quarter — a real, if delayed, window into what the biggest players actually own.
Start Lesson Practice this topicWhat an S-1 Is, and What to Look for in a Company Going Public
Before a company's stock ever trades publicly, it has to tell the world everything material about its business in one enormous document — read that first, not the hype.
Start Lesson Practice this topicWhat a Restatement Is, and Why It Is a Serious Red Flag
When a company admits its own past financial statements can no longer be trusted, that's not routine housekeeping — it's one of the most serious signals a filing can send.
Start Lesson Practice this topicHow to Spot the Difference Between a Company That Is Transparent and One That Is Hiding Something
The same underlying bad news can be disclosed two very different ways — and how a company chooses to say it often tells you as much as what it says.
Start Lesson Practice this topicIntermediate Investing
2 lessonsHow to Read Financial Statements
Learn how to analyze income statements, balance sheets, and cash flow statements.
Start Lesson Practice this topicUnderstanding Revenue Growth
Learn why revenue growth is one of the strongest indicators.
Start Lesson Practice this topic