It never ceases to amaze me the lengths email scammers will go to persaude you to divulge personal information …the techno term is Phishing.
The emails can be constructed to look like they have come from your bank, credit card company etc, with branded graphical elements and links that look like they are going to take you to the bona fide web site.
If you follow the links you reach what appears to be the bona fide site … it will have been designed exactly like the real thing. Enter your user name and password and bingo the scammer has your personal information that can be used on the genuine site.
The best policy is to be highly suspicious of any email asking you to log in via a link within the email.