Your choice of which mechanism to use depends on which operation you are performing, importing or exporting, and the format of the data, text or binary. When you use the Import Wizard, you do not need to know the format of the data. You simply specify the file that contains the data and the Import Wizard processes the file contents automatically. For more information, see Using the Import Wizard with Text Data and Using the Import Wizard with Binary Data Files .
Binary files contain data that represents images, sounds, and other formats.
See Working with HDF Data for more information.