Prediction Markets Explained

How Event Markets Turn Prices Into Probabilities

Sponsored•September 17, 2026, 4:14PM EDT
Beginner
UPDATED: October 7, 2026, 7:01AM EDT
Prediction Markets Explained

Direct answer

A prediction market is a marketplace where participants trade shares linked to the outcome of future events.

A share that resolves correctly pays out a fixed amount, while an incorrect share expires worthless. Because the share price reflects what traders are willing to pay, the market price can be read as an implied probability.

 

We'd love your feedback.

Advertisement

Prediction markets let participants buy and sell shares tied to real-world outcomes. Because prices move as traders react to new information, these markets can act as continuously updated probability signals for elections, policy decisions, crypto events, business outcomes, sports, and more.

Why prediction markets matter

Prediction markets are powerful because they aggregate information through market incentives. Thousands of participants can act on different information, models, and expertise. As they buy and sell shares, the resulting price becomes a crowd-sourced probability estimate that updates as new information comes in.

That does not make a market price a guarantee. Price, volume, liquidity depth, and resolution quality all matter. A price move backed by deep volume and liquidity can be a stronger signal than a thin market with little trading behind it.

How prediction markets developed

Prediction markets grew from academic and experimental event markets into online platforms covering politics, economics, technology, sports, and other outcomes.

Projects such as the Iowa Electronic Markets and Intrade helped establish the model. Crypto-native platforms later added blockchain settlement, stablecoin-denominated shares, and transparent smart-contract rules.

What you’ll learn

The lesson summaries below give a short overview of the full course content. Take the full interactive Prediction Markets course to explore each lesson in more depth through guided explanations, examples, and activities.

Lesson 1: Introduction and History

This lesson defines prediction markets, traces their evolution from academic experiments to modern crypto-native platforms, and explains why they have become mainstream information tools.

Key terms include prediction market, event market, implied probability, and wisdom of crowds.

Lesson 2: How Prediction Markets Work

This lesson explains Yes and No shares, price-as-probability, financial incentives, binary markets, categorical markets, scalar markets, order books, AMMs, and how prediction markets differ from sportsbooks.

Key terms include binary market, order book, AMM, liquidity, bid, and ask.

Lesson 3: News and Information Signal

This lesson explains how prices, volume, liquidity depth, and cross-market comparisons can be read as real-time information signals.

Key terms include information signal, volume, liquidity depth, and cross-market analysis.

Lesson 4: Polymarket as a Case Study

This lesson uses Polymarket as a case study for crypto-native prediction markets, including USDC settlement, on-chain transparency, market breadth, and platform design.

Key terms include Polymarket, Polygon, USDC, and on-chain settlement.

Lesson 5: Technical Infrastructure

This lesson introduces blockchain settlement, smart contracts, oracle-based resolution, share splitting, and market creation at a conceptual level.

Key terms include smart contract, oracle, resolution source, Neg Risk, and share splitting.

How prediction markets work

A prediction market usually follows a simple structure:

  • A market asks a clear event question with defined outcomes.
  • Participants buy Yes, No, or outcome shares tied to that event.
  • Prices move as new information arrives and traders update their views.
  • Volume and liquidity help determine how strong or fragile the signal is.
  • The event resolves through a defined source, ruleset, or oracle process.
  • Correct shares pay out; incorrect shares expire worthless.

Binary markets have two possible outcomes, while categorical markets offer several mutually exclusive choices. Scalar markets represent a value along a range.

Platforms can match participants through an order book of bids and asks or use an automated market maker that quotes prices from a liquidity pool.

Prediction markets vs sportsbooks

Both structures concern uncertain outcomes, but their market design differs.

A sportsbook sets odds and usually acts as the counterparty to the bettor. A prediction market issues tradable outcome shares whose prices move as participants submit orders or trade against available liquidity.

The distinction affects pricing, liquidity, settlement, and the legal framework that may apply.

Key differences

  • Counterparty: In a prediction market, the counterparty is usually other market participants. In a sportsbook, the counterparty is usually the house.
  • Pricing: Prediction market prices move through supply and demand. Sportsbook odds are set by the bookmaker.
  • Position structure: Prediction markets use tradable outcome shares. Sportsbooks use bets or wagers.
  • Exit before resolution: Prediction market participants can often sell shares before the event resolves. Sportsbook exits are usually more limited.
  • Information signal: Prediction market prices can be read as market-implied probabilities. Sportsbook odds include bookmaker pricing and margin.
  • Core purpose: Prediction markets are designed around forecasting and event pricing. Sportsbooks are designed around wagering on outcomes.

Polymarket as a case study

Polymarket provides a case study in crypto-native prediction markets. It shows how a platform can combine event-market design, on-chain settlement, USDC-denominated trading, market resolution, and user-facing tools to make prediction markets accessible at scale.

This page treats Polymarket as an educational case study, not as a recommendation or call to trade.

Technical infrastructure at a high level

Crypto-native prediction markets depend on specialized infrastructure. At a high level, this includes:

  • lower-cost blockchain settlement;
  • stablecoin-denominated payouts;
  • smart contracts;
  • oracle-based resolution;
  • mechanisms that keep Yes and No shares economically linked to the final payout.

Some designs let collateral be split into complementary outcome shares and recombined when the complete set is present.

Multi-outcome markets may use additional accounting rules so overlapping outcomes do not create inconsistent exposure. The exact implementation varies by platform, but every design needs clear resolution criteria and a credible dispute process.

Risks and trade-offs

Prediction markets can be useful information tools, but they are not perfect forecasting machines.

Key risks include:

  • Thin liquidity: A market with little trading may produce a weak or noisy signal.
  • Poorly written market questions: Ambiguous wording can create confusion at resolution.
  • Resolution disputes: Participants need confidence that the outcome source and dispute process are credible.
  • Legal and regulatory uncertainty: Prediction markets may be treated differently depending on jurisdiction, market type, and platform design.
  • Overreading probabilities: A price is not a guarantee. It reflects market activity under specific conditions.

Educational disclaimer: This page is for educational purposes and explains prediction market mechanics. It does not provide investment, trading, gambling, legal, or tax advice.

Before you start

This topic is intended for readers who want a clearer understanding of event markets, probability signals, market structure, and crypto-native settlement.

Familiarity with crypto transactions, stablecoins, exchanges, order books, and smart contracts is helpful.

Glossary

Prediction market

A market where participants trade shares tied to future event outcomes.

Implied probability

The probability suggested by the market price of an outcome share.

Yes share / No share

Outcome shares that pay out depending on whether an event resolves yes/true or no/false.

Binary market

A market with two possible outcomes.

Categorical market

A market with multiple mutually exclusive outcomes.

Scalar market

A market designed for a continuous value or range.

Order book

A list of bids and asks where buyers and sellers meet.

AMM

An automated market maker that uses a pool of capital and an algorithm to offer prices.

Oracle

A system used to bring event outcomes or external information into a smart contract process.

Resolution source

The source or rule used to determine how a market resolves.

Continue learning

Prediction markets connect naturally to several Campus topics.

Market Structure 201 helps explain order books, liquidity, volume, spreads, market makers, and execution quality.

DeFi 201 provides context for AMMs, oracles, and composable protocols.

Ethereum & Layer 1s 201 explains smart contracts and settlement assumptions.

Scaling & Layer 2s 201 helps frame Polygon and lower-cost blockchain execution.

Start the full interactive course

This guide covers the mechanics of prediction markets. The full Prediction Markets course goes deeper with guided explanations, examples, interactions, platform context, knowledge checks, feedback, progress tracking, and completion.

Start the full interactive Prediction Markets course to understand how event markets work, how prices become probability signals, how Polymarket illustrates the model, and how crypto infrastructure supports on-chain prediction markets.

 

 

Continue on Campus

Ready to take the full course?

Get access to Campus for free. Create an account to explore courses, track your progress and earn a certificate.

  • Build your knowledge
  • Track your progress
  • Get certified
Try Campus free

Campus is a premium platform – start with a free trial. You'll be redirected to Campus to sign in.

How we made this

This explainer is written and maintained by The Block's editorial team, reviewed against primary sources and protocol documentation, and updated as the space changes. Where AI tools assist drafting, a human editor reviews and edits before publishing.

© 2026 The Block. All Rights Reserved. This article is provided for informational purposes only. It is not offered or intended to be used as legal, tax, investment, financial, or other advice.

ASSETS MENTIONED IN THIS ARTICLE

Related explainers

see more in learn: Sponsored

Related prices

Token Prices

Token Price Change
$82,979.16-4.06%
$2,561.51-5.78%
$0.999732-0.02%
$766.33-2.41%
$1.43-6.18%
see all prices

Frequently asked questions

If a Yes share trades at $0.65, the market is pricing that outcome at about 65%, before fees or market frictions.

 

No. Prediction markets use tradable shares and participant-driven pricing, while sportsbooks set odds and act as the counterparty.

 

Polymarket is a decentralized, crypto-native prediction market platform launched in 2020 by Shayne Coplan that runs on the Polygon blockchain network.

 

Clear questions, reliable resolution sources, sufficient liquidity, transparent rules, and credible dispute mechanisms all matter.