Exporting a Parts List, is an important feature when you need a check list, or even a shopping list. This feature can be found in the View > Part List menu.
You can split the list by brick layer if desired by checking the box at the bottom of the window.
To save the list press the "Export..." button. You can save the file as a regular text file, or an HTML file if you want pictures of the parts included in the list. The pictures of the parts are referenced on internet, which makes the file portable (you can send it to your friends), but of course requires an internet connection to be displayed correctly.
You can print the parts list by opening the .txt or .html file which you exported using the "Part List" export feature, and using the print command provided by the software that opened the file.