How much is net working capital?

Excuse me, could you kindly clarify for me what exactly is meant by "net working capital"? I understand it's a financial metric, but I'm not entirely sure how it's calculated or what it represents in terms of a company's financial health. Specifically, I'm curious about the exact formula used to determine the amount of net working capital and how it can be interpreted to evaluate a business's liquidity and operational efficiency. Is it simply the difference between current assets and current liabilities, or is there more to it? Your insights would be greatly appreciated.