This is a simple income tax calculation tool. As you know, the tax code is incredibly complex and includes hundreds of tax forms and countless rules. This tool (as well as every other tool) makes no attempt to cover everything. It only attempts to include the most common requirements of low-income tax filers. This is a tools for planning and analyzing tax various tax situations; not for filing your taxes.
As with other tools in the TAXTools toolset, the places where you enter information are green. This is particularly noteworthy on the input tax forms (for example, W-2, 1099-R). Each tax input form, has many fields (they are usually numbered boxes on input tax forms); however, only some of the fields are green. The reason for this is that the green fields are used by the tool to calculate the tax and the other fields are not used. It is not they they are not needed to accurately determine the tax, but they are not implemented by this tool.
Because there may be a lot of information entered into this tool, you can click the Save button at anytime to save the data that has been entered so far. This will save the data to a text file named TaxProgram.txt in your Downloads folder (at least that is where is saved on Windows). Restoring the file will completely reset the tool and reenter the data from the file.
The remainder of this document describes the fields were you can input information. This is also the same information that is displayed in the tooltips.