What is the difference between signing up as a co-author and not? If you do not sign up, you can only post in our comment section and comment is not visible until click on. If you sign up as co-author, you can post your own publication. Your post will be publish on the main page. You can also publish photos and videos from your computer files. As we have said you can always manage your post for editing or deletion even after publication. You can even embed YouTube and other link in your post. Just make sure your post are about bicycling or other very interesting sports events. No on political or religious topics, except holiday greetings.