Working capital refers to the funds required by a business to meet short-term operational expenses. Gross working capital is the total capital invested in current assets, while net working capital is the excess of current assets over current liabilities. Current assets include cash, receivables, inventory, and prepaid expenses, while current liabilities include bills payable, creditors, loans, and outstanding expenses. Factors like the nature of business, production cycle, and growth influence working capital needs. Both too little and too much working capital can hurt business operations and profitability. Sources of working capital include retained earnings, reserves, depreciation funds, shares, debentures, loans, and public deposits.