can work on the same page at the same time using OneNote as a shared whiteboard environment. On March 17, 2014, Microsoft released the OneNote cloud service API that enables third-party application developers to integrate the service into their apps. The API runs on Microsoft's globally available cloud and sends data from applications into the user's OneDrive. OneNote can perform optical character recognition on images of text and can render webpages as snapshot images. Microsoft also announced several new features in OneNote that use the service API: OneNote Clipper: A browser bookmarklet that uses the OneNote service API and enables users to save a screenshot of a webpage to OneNote along with the link. The text in the screenshot is made searchable using Optical Character Recognition. Email to OneNote: A feature enabling users to send emails to the address me@onenote.com from pre-specified email IDs to have the contents of the email saved to OneNote. File format A OneNote notebook is stored as a folder with a separate data file for each section. A .one file can be a OneNote notebook or a OneNote section. OneNote files have a .one filename extension. Microsoft upgraded the file format twice after it had introduced OneNote 2003 — first in OneNote 2007, then in OneNote 2010. OneNote 2003 files can be opened by both OneNote 2007 and OneNote 2010 in read-only mode and subsequently upgraded to the later versions of the file format. OneNote 2010 can read and write OneNote 2007 file formats. It can also convert back and forth between the 2010 and the 2007 formats. Microsoft has documented the OneNote file format. It is an open format that can store varied multimedia content in a single .one file. Multiple .one files can be exported to a .onepkg file, which stores multiple .one files (corresponding to the individual notebooks) in cabinet file format. Platform support OneNote supports simultaneous editing of shared OneNote documents by multiple users when the document is stored in a shared folder in OneDrive. Dropbox was supported for some time as a sync protocol, but after Windows Live Mesh was discontinued, OneNote supported it for cloud-based storage and synchronization of OneNote files. OneNote clients, including the OneNote web app of Office Online, can view and edit them. Microsoft made OneNote 2013 for Windows desktop available for free. OneNote for Windows and Mac are both based on a freemium model. Premium