File Comparison feature compares two files (either binary or text). It can be used, for example, to locate all changes you have made to a file. After the operation completes, the File Comparison Tool Window contains comparison results. In addition, corresponding areas are highlighted in the editor.
To change colors used by the file comparison feature, press the Select Colors… button on the File Comparison Tool Window's toolbar.
To compare files execute the Tools » Compare Files… command.