GnuCash is a personal and small-business financial-accounting software, freely licensed under the GNU GPL and available for GNU/Linux, *BSD, Solaris and Mac OSX. GnuCash is designed to be easy to use, yet powerful and flexible, GnuCash allows you to track bank accounts, stocks, income and expenses. Also, it can function as a quick and intuitive program to use as a checkbook register, as it is based on professional accounting principles to ensure balanced books and accurate reports.
So, what can GnuCash do for you? It can keep track of your personal finances in as much detail as you prefer. If you are just starting out, use GnuCash to keep track of your checkbook. You may then decide to track cash as well as credit card purchases to better determine where your money is being spent. When you start investing, you can use GnuCash to help monitor your portfolio. Buying a vehicle or a home? GnuCash will help you plan the investment and track loan payments. If your financial records span the globe, GnuCash provides all the multiple-currency support you need.