Discusion vs. Forum DIFFERENCES?

Discusion vs. Forum DIFFERENCES?

Hello,

What is the difference between Zoho Discussions and Forums.  Also, can my Forum created in the Business application only be access through the Business application.  Can the Forum or discussion application be embedded into another webpage the way you allow other application code to be embeded.

I noticed that the URL to Zoho Discussions is not available on Zoho Home nore is the Forum.  I found the direct link to Discussion/Forum in an email notification to saying that "You are receiving  this eamil because you are watching radhakswamy." 

Do I get notified via email when I put someone on my whatchlist and/or also when I click in a Topic "notify me on response" AND how do I disable that.  I am getting email notifications and can't turn it off.  Thank you.
George Polzer