A line of credit can be used as a security blanket for your business. If you need the capital, it's there to be drawn upon. However, there is no obligation to use it, and you are only responsible for paying interest on the amount withdrawn. As you pay into it, the funds become available for use again. Most lines of credit also appear as positive items on a credit report.
After approval for a line of credit, the business will have capital available to be drawn upon, like a credit card. Upon request, cash can be deposited to your business checking account and used to fund your business needs.