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Investing 101

Picking & holding stocks

Only worth reading once you have decided to do the extra work. What a business is worth, what protects it, and what should make you change your mind.

16 guides · Beginner friendly

Valuation6 min read

What a P/E Ratio Is, and the Comparison That Makes It Useless

The most quoted number in stock picking, and the one most often misused. What it actually measures, and why comparing it across two industries produces a confident wrong answer.

Based on a clip by @seekingwisdominvesting YouTube

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Valuation9 min read

"If You Can't Answer This, Don't Buy the Stock" — Buffett's Test in One Question

One answer at a university Q&A, and the cleanest statement of what a share is. Intrinsic value is all the cash a business will hand you, discounted — which makes valuation three questions, and makes "I can't answer that" a complete decision rather than a gap to be filled with optimism.

Based on a clip by @YAPSS YouTube

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Fundamentals7 min read

Three Statements, Three Questions

A company's accounts look impenetrable until you know that each of the three statements exists to answer exactly one question. Learn the three questions and the layout stops mattering.

Based on a clip by @BrianFeroldiYT YouTube

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Valuation13 min read

How to Tell Whether a Stock Is Cheap — Three Methods, and Why You Need More Than One

Cheap has nothing to do with the share price. Three ways to estimate what a business is worth, what each one assumes, and why the honest answer is to run more than one and look for agreement rather than precision.

Based on a clip by @TheSwedishInvestor YouTube

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Screening6 min read

The Four-Number Stock Checklist — Which Parts Survive

Four numbers, one score, ten minutes a stock. The structure is genuinely useful for a beginner — but one of the four rewards you for buying what has already gone up.

Based on a clip by @joyeeyang YouTube

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Screening9 min read

Two Numbers: Cheap, and Good

Greenblatt reduced stock selection to two rankings added together. The interesting part is not the formula — it is his explanation of why it cannot be arbitraged away.

Based on The Little Book That Beats the MarketJoel Greenblatt

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Quality10 min read

Economic Moats: The Four Things That Actually Keep Competitors Out

A great product is not a moat. Neither is great management. There are four structural advantages that keep high returns from being competed away, and they are checkable.

Based on The Little Book That Builds WealthPat Dorsey

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Quality9 min read

What a CEO Does With a Dollar Decides Everything

Thorndike studied eight CEOs who massively outperformed their peers. None was a visionary operator. What they shared was a discipline about where the company's cash went.

Based on The OutsidersWilliam N. Thorndike

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Principles11 min read

Warren Buffett's Six Rules of Investing — Which Ones Transfer to a Small Account

Six principles, in Buffett's own words, cut from interviews. The words are real and mostly excellent. The numbering is the editor's, and it hides the fact that rule five only works if rules three and four are already true.

Based on a clip by @TheBetterMenProject YouTube

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Research11 min read

"Invest in What You Know" — What Peter Lynch Actually Said, and the Half Everyone Drops

A compilation of Peter Lynch talking to a room of investors. Four ideas run through it — know what you own, stop predicting, declines are scheduled, and you are in no rush — and the famous one about investing in what you know is the one that has been flattened the most in the retelling.

Based on a clip by @thecooperacademy YouTube

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Research10 min read

Peter Lynch's Six Categories: Sort the Company Before You Value It

Lynch's first move was never valuation. It was sorting the company into one of six buckets — because what you should expect, and when you should sell, is decided by the bucket.

Based on One Up on Wall StreetPeter Lynch

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Research10 min read

Scuttlebutt: How to Research a Company Without an Analyst's Access

The most useful information about a business is held by the people who compete with it, buy from it, and used to work there. None of it is in the annual report, and all of it is reachable.

Based on Common Stocks and Uncommon ProfitsPhilip A. Fisher

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Screening10 min read

CANSLIM Explained — Seven Filters, and the Two That Do Most of the Rejecting

A seven-letter checklist that is unusually specific about its thresholds, and unusually demanding about when you are allowed to trade at all. Worth understanding as a screen — and worth being careful with the return figures attached to it.

Based on a clip by @RichardMoglen YouTube

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Momentum6 min read

Buying at the 52-Week High: The Research Behind the Ugliest-Feeling Entry

The research the video leans on found that nearness to the 52-week high predicted future returns better than past returns did — because traders anchor on the high and under-react to good news. It is a portfolio-level tendency, not a promise about any single breakout.

Based on a clip by @lookingatthemarkets YouTube

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Selling9 min read

When Not to Sell a Stock — Buffett Gave Two Opposite Answers, and Both Were Right

A student asks how he decides to abandon a position. The answer is four minutes long, contains two contradictory rules, and the contradiction is the lesson: what you should do about selling depends on whether you are short of ideas or short of cash.

Based on a clip by @YAPSS YouTube

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Mistakes10 min read

Buffett's Biggest Mistakes — The Expensive Ones Never Showed Up in the Accounts

A list of admitted errors that ends somewhere unexpected: the trades that lost money were not the expensive ones. The mistakes that cost most were the good ideas he understood and did not act on — and nothing in any accounting system records those.

Based on a clip by @YAPSS YouTube

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Stock Picking Guides: Valuation, Moats and When Not to Sell | Plutux