Liquidity describes how quickly and easily something can be turned into cash without losing much value. Cash itself has perfect liquidity because it's already cash. A savings account has high liquidity because you can withdraw money anytime. But a house has low liquidity because selling it can take months and involves complicated paperwork.

Think of liquidity like the difference between having a twenty-dollar bill in your pocket versus owning a rare baseball card worth twenty dollars. The bill is instantly spendable anywhere. The card might be valuable, but you'd need to find a buyer, agree on a price, and complete the sale. That's the difference between liquid and illiquid assets.

Banks and businesses worry about liquidity constantly. A store might own lots of inventory but struggle to pay employees if nobody's buying anything that week. The store's wealth is tied up in merchandise that isn't liquid enough to cover immediate expenses.

When people talk about a liquidity crisis, they mean someone (or some business or country) owns valuable things but can't convert them to cash fast enough to pay bills. Having wealth and having liquidity aren't the same thing. You can be rich on paper but cash-poor in reality.