What are the two usages for the term working capital?

The most common meaning for the term working capital is the difference between current assets and current liabilities:

In this usage, working capital is the dollar amount of current assets left over after the remaining current assets are allocated to pay the company’s current liabilities. These “extra” current assets can be used to finance the ongoing work of the business, hence they represent the firm’s “working capital.” The second meaning for working capital is total current assets:

When working capital is used in this second way, the term net working capital is often used to stand for current assets minus current liabilities: