Working capital
The money tied up in running the business day to day: stock, money customers owe you, minus what you owe suppliers.
Working capital is the cash a business needs just to keep going between paying for things and being paid for them. More stock, or customers who pay later, means more working capital; suppliers who give you credit mean less.
A business can be profitable and still short of working capital — especially while it is growing. Banks lend for it separately from loans for equipment.
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See also: Cash flow, Break-even