stock market

Stock market crashes are not random events. They follow a mechanical sequence: valuations stretch on borrowed money, a trigger breaks confidence, and forced selling feeds on itself until buyers disappear.

Learn how stocks, exchanges, IPOs, valuation, and market indices work — from bid-ask spreads to the efficient market hypothesis.

The United States held $62.2 trillion of listed company value at the end of 2024, 54% of the world total in World Bank data. This ranking of the largest stock markets shows who follows, why one country dominates, and why some 2025 figures need care.

What a share really is, how exchanges match buyers and sellers, how prices are set, what indices measure, why crashes happen, and how regulators keep the system running. Here's how stock markets actually work.