When you get the request, you can accept, ignore or block/report them.
Yes it's common and very easy. i can put a trojan in a friend request and all you need to do is click and i have you
Yes
No. It means that the friend is now offline.
If they are your friend on fb then you can chat if no your friend add them
From fb: How do I remove or cancel a friend request I made to someone? Visit the person's profile and click the "Cancel Friend Request" link... Visit the person's profile and click the "Cancel Friend Request" link underneath the profile photo. After you click this, the link will say "Friend Request Canceled" in grey letters.
The only way to know if your friend request has been declined is to request to be their friend again. If it lets you re-request, then they denied your friend request.
An Un-accepted friend request or incoming friend request
Log into your Email account (the one you get FB mails to). Open the FB mail, or tick it. Go to options and choose report to spam. After a while FB would stop Emailing you.
FB friend refers to the relationship between two friends that are connected on Facebook.com.
Go to edit and then go to ur friends
You go to your notifications and then look for the friend request. :-)