Liquidity refers to how quickly and smoothly an asset can be traded. A highly liquid market has many active buyers and sellers, so trades can be entered and exited easily and prices tend to move in an orderly way. A market with low liquidity has fewer participants, which can make it harder to trade and can cause prices to jump more sharply. Liquidity matters to traders because it affects how easily they can get in and out of positions and how stable prices are. It is closely linked to the spread — more liquid markets usually have tighter spreads.