AAF (Advanced Authoring Format) is used by other DAW applications such as Pro Tools. You can use it to import multiple audio tracks, inclusive of references to tracks, time positions, and volume automation.
Choose File > Export > Project as AAF File.
In the Save AAF File As dialog, set the following options:
Sample Rate: Choose 44.1 kHz, 48 kHz, 88.2 kHz, or 96 kHz.
Bit Depth: Choose either 16 or 24 bit.
File Format: Choose WAVE or AIFF.
Dither Type: Choose None or any of the four dither algorithms (see About dithering algorithms).

Choose a location, enter a name for the file, then click OK.
The export includes all used regions, inclusive of track and position references and volume automation.
Do one of the following:
Choose File > Import > AAF, then select a file in the dialog that appears.
Locate and select the AAF file in the All Files Browser, then click Open.
Choose File > Open.
Choose the AAF file in the Open dialog.