Each collaborator chooses a color to indicate changes they have made. In the right sidebar you will see those who are currently collaborating and a chat window.
Beneath the sidebar there are buttons allowing you to hide/show the sidebar and toggle the use of the whole window. In order to get more use out of TypeWith.me, check out the tool bar along the top of the screen. The options menu allows you to enable/disable authorship colors and the line numbers and to change the font type.
There are several file formats you can import and export.
One of the cool features of TypeWith.me is that you can save the document at any time and you can revert to any point you have saved in the past.
Another cool feature is the Time Slider which lets you go back and watch a recording of the document being worked on. The stars indicate points that have been saved.
Each online document has its own unique URL you can share with others for real-time co-editing, and there's a small window for chatting on your edits. TypeWith.me helpfully assigns different colors to each author so you can easily track who's typed what, and the app instantly synchronizes as you type so changes appear in real time. When you're done, export your work to one of six file formats, including Word, PDF, and HTML.