Cash Flow is the term used to describe the activity of cash moving in and out of the business. For example cash coming in from sales, loans, interest etc. and cash going out e.g. expenses, taxes, dividends etc.
Cash Flow Forecast is a report that shows the movement of cash into and out of the business, as well as the opening and closing bank balance each day, week, month etc. The Cash Flow Forecast is probably the most important financial management tool in any business. It sets out clearly where the Cash Flow issues will be in the future, which provides an opportunity to deal with it well in advance.