OneNote is designed to allow hierarchical organization of information. This is achieved with grouping into the following categories and UI elements (Notebooks, Sections, and Pages). Both Sections and Pages allow additional groupings that can be expanded/collapsed in list view.

This can be incredibly helpful for quickly taking notes and organizing them for work or personal projects.

For example, you could have a Notebook for "Cooking Recipes", with sections for "breakfast, dinner, desserts", where individual recipes would be page entries (i.e. the "Desserts" section would have pages for brownies, chocolate cheesecake etc).

OneNote is available for free as a web app as well as natively on iOS, Android, OSX, and Windows. You can also use OneNote for free on as many devices as you need, through Cloud syncing.

OneNote allows you to arrange text freely on the digital paper mimicking the way it would be done with a real pen on real paper.

If you have experience with other Microsoft programs such as Microsoft Office, you'll feel right at home with the design of OneNote thanks to the similarity of the menus. OneNote also integrates with Outlook, Office, and OneDrive.

OneNote can be used on all touch capable devices via stylus or digitizer pen, making for an intuitive and easy way to take notes by hand, which can often be faster or just preferred over typing.

Can have multiple 'tabs' at the top like in a web browser with many notes within each 'tab'.

You can add a variety of different files into your notes including images, video, audio, web clippings and more.