- People with the same interest can interact with each other.
- Author of any content is available to answer any query.
- Real time updates.
You can build this system in whatever language you are comfortable with.For eg JSP,PHP,C# or Ruby but I would suggest you to use Content Management system(CMS) such as Drupal, Joomla or Ruby on Rails.Advantage with CMS is that it helps you to keep focus on project and remaining things would be handled by it.
Any Authenticated user can write an article and share it with other users. Users with or without authentication can read any article written on the site and can also comment on it
If you are using CMS. It is very easy. You need to define role of users and give them permission accordingly. In drupal you can add or set permission using “People” option of Administrator toolbar.
Administrator : read,write,delete and edit any article and comment.
Authenticated: read any article and write,edit and delete his own article.
User: read any article on given page
How to build it?
Building it is very easy using drupal(requires php and mysql).You just need to download and install drupal into your system.Everything from authentication,commenting,Permissions and Roles would be handled by drupal.