Cash flow is the sum of money that comes into and goes out of a business or person's bank accounts over a certain amount of time. It shows the net change in the cash balance of a person or business, taking into account cash inflows (like income, loans, or investments) and cash outflows (like spending, paying off debt, or investing). Positive cash flow happens when the cash coming in is more than the cash going out. This means that cash assets are growing. Most people think this is a good thing because it means bills can be paid, growth can be invested in, and unexpected costs can be handled. On the other hand, cash flow is negative when cash losses are greater than cash inflows, which causes cash reserves to go down. It can mean that there are problems with money and that you need to do things like get more money, cut costs, or rethink your business strategy.