Spam is the most common form of unwanted email. It is annoying and can be sent in large quantities. They can fill your inbox with unrequested emails, typically, but not always, with a malicious intent. The identity of the sender is anonymous and there is no option to stop receiving future emails.
Gmail has a spam filter that automatically labels suspicious emails as Spam. If an email is labeled as spam and should not be, open the email and then click the button Not spam.
