The Facts About Income Tax Millions faithfully file their 1040 forms each April. But some things about federal income taxes may surprise you. Share | Related Content Comparing Investments This calculator compares the net gain of a taxable investment versus a tax-favored one. How to Make the Tax Code Work for You When you take the time to learn more about how it works, you may be able to put the tax code to work for you. Tax Management Strategies Learn more about taxes, tax-favored investing, and tax strategies.