Commodities 101: What Moves Oil, Gold, and Grain Prices

A commodity is a raw physical good — oil, gold, natural gas, wheat, copper, and dozens of others — that's largely interchangeable regardless of who produced it. A barrel of a given crude oil grade is essentially the same barrel no matter which company pumped it, which is what makes commodities tradable as a standardized asset rather than a unique one like a company.

Commodity prices are driven almost entirely by supply and demand fundamentals in a way that's more direct than stocks: a drought cuts wheat supply and prices rise; a mild winter cuts natural gas demand and prices fall. Weather, geopolitics, production disruptions, and inventory levels move commodities more immediately than the kind of sentiment-driven swings common in stocks.

Most individual investors don't take physical delivery of oil barrels or gold bars. The common ways to get exposure are: commodity ETFs (holding futures contracts or, for gold/silver, sometimes the physical metal itself), shares of companies that produce the commodity (an oil driller, a gold miner), or futures contracts directly (an advanced, leverage-heavy tool covered in the next lesson).

Gold in particular gets treated differently from other commodities — it's widely held as a perceived safe-haven and inflation hedge rather than for industrial use, so it often behaves differently during market stress than industrial commodities like copper or oil, which tend to fall alongside broader economic slowdowns rather than rise.

Commodity investing carries a structural quirk beginners often miss: commodity ETFs that hold futures contracts (rather than the physical good) can lose money from 'roll costs' — the cost of rolling an expiring futures contract into the next one — even if the spot price of the commodity itself doesn't move at all. That's covered in more depth in the Advanced lesson.