spam e-mails

There are few things that you can look for for example if in the end of the email you do not see a link to unsubscribe to this email then this is surely a spam.Most of the Legit sites attach unsubscription link in the end of their emails so that if a user no longer wish to receive emails from them regularly , then they can unsubscribe using that link.Spammers will not attach such links to their emails.

look at the header and body of the message. also if it's not from a friend or something you subscribed to on the net, it's more than likely spam.