Phishing scams can cause massive disruption in people’s lives, you are tricked into believing that you’re typing your information into say your bank’s website or Facebook, etc. when in reality your typing your information into a site that appears to look like them but really isn’t.
Many companies are trying to combat this when they send you an email regarding your account, for example, Discover puts in their emails “Add [email protected] to your address book to ensure delivery of these emails. See ways to help identify authentic Discover emails by visiting our email security page.”
The easiest way to tell if you are typing your information into the real site or a phishing one is by checking the URL each time.