Similarities:
They both are ways to reach out to advertise products through the use of technology making them seen by a very wide range of buyers
Differences:
Emails are ignored and deleted by lots of people making them less effective however people may still see them unless they go to junk mail. Regular online advertising however, might reach more people as they might appeal more with photos or slogans to help get the advertisment stuck in the buyers mind. In my opinion, online advertising is more effective than emails.
