In the financial market, trading liquidity is crucial. It refers to the ability of an asset to be quickly and cheaply converted into cash without significantly affecting its price. High liquidity markets, such as popular stocks or mainstream foreign exchange trading, have active buying and selling, narrow spreads, and investors can quickly enter and exit; while low liquidity markets have sparse trading, difficulties in buying and selling, and high costs. It affects trading costs, efficiency, and investment strategies, and is a key factor in the healthy operation of the market.