Lessons · Markets · Beginner
Supply, demand, and price discovery
Markets clear where willing buyers and sellers meet. Price discovery is that continuous negotiation.
7 min read
What you will learn
- Explain price discovery simply
- Connect news to shifts in supply and demand
- See why order flow and liquidity matter
Key terms
- Price discovery
- The process of finding a clearing price through trading.
- Order flow
- The stream of buy and sell interest hitting the market.
- Clearing price
- The price where quantity demanded matches quantity supplied.
1. Auctions, not oracles
A last trade is simply where the latest buyer and seller agreed. New information shifts willingness to pay or sell, and the auction moves.
2. News as demand shock
Guidance cuts, rate surprises, and geopolitics change demand schedules quickly. Gaps happen when overnight information arrives before continuous trading resumes.
3. Why thin books hurt
When few orders rest on the book, each trade moves price more. That is liquidity risk in action.
Overnight gap
A company warns after the close. Buyers pull bids; sellers hit lower asks at the open. The gap is supply and demand resetting.
Common mistakes
- Believing the last price is true value rather than a clearing print
- Ignoring that holidays and halts pause discovery
- Assuming deep liquidity in every name at every hour
Try this on StockWatch
- Watch how headlines and upcoming events cluster with big gaps
- Compare liquid index names vs thinner single names
- Use the news desk to see what shifted demand overnight