Microsoft is making it a little easier to collaborate on Office documents over the Web by letting users edit files without signing in.
Previously, users needed a Microsoft account in order to edit other people's documents using Office Web Apps. In a blog post, Microsoft noted that users, especially students, became frustrated if they were just trying to make a quick edit and were forced to sign in or sign up for an account along the way. Now, all they need is an edit link.
To create an edit link in Office 2013 or in Office Web Apps, go to the "File" menu and click the "Share" tab. In Office 2013, you'll see a "Get a Sharing Link" option, with buttons to create links for editing or for viewing only. In Office Web Apps, you'll see a "Share with Other People" option, followed by an option to "Get a link." From there, look for options to create "View only" or "View and edit" links.
Keep in mind that Google Docs has offered editing without a login for a while now. After creating a share link, the user has an option to specify who has access to the document, and from there, an option to allow editing, commenting, or just viewing privileges to users without a sign-in.
However, Microsoft's approach is slightly more powerful because it lets you create separate links for viewing and editing. That means you can give editing privileges to a small number of people while sharing a file more broadly, with no need to create a whitelist of specific users within the software.
From now on, if you want to require a sign-in through Office Web Apps, you must use the email ink prompt within Office, then look for the required sign-in check box.