Your current net worth is defined as everything you have minus everything you owe, or your assets minus your liabilities.
The greater your net worth, the richer you are. The earlier you start saving and building wealth, the richer you will be. You can calculate your future net worth to see what your wealth creation will look like over many years.
Tracking your net worth throughout your life will give you a more encapsulating understanding of your financial health than simply tracking expenses. For most, an increase of net worth comes through the saving of job income and appreciation in value of one's home and investments. Many saw a major swing in their net worth with the real estate boom over the past years.