I am new to sharepoint online. At first I need to know the difference between sharepoint online and office 365 preview.
Preview site: https://portal.microsoftonline.com/Admin/Default.aspx which looms like below.
I have also the below site
Now what is the difference between the two. My goal is to create apps and webparts. Which one shall i choose? I have not installed sharepoint 2013 server/ sharepoint foundation. Can i create apps and webparts without installing server2013/foundation2013?