What is the difference between Contacts and Subscribers in Salesforce Marketing Cloud 

awesome! really really apreciated your effort to help people using this tool. I can't wait to see your tutorial about deleting contacts, thanks again.

Thank you! This was great and I am a complete beginner in SFMC.

Great explanation

Great clip mate, thanks for this. I am really going HAM to skill up in SFMC. Going for the Admin cert next month and looking to get MC consultant cert not long after!

If we have 2BUs in one account then does we count all the Contacts from both BUs or only from production BU ?

Hello there! I'm adding a new record into an existing DE for some test (email address is my primary key and is sendable), but I can't find this record into my "AllContact" section. Probably because is not used into an email? Then I sent an email to myself, despite the platform was saying "email sent" I haven't receive any email, and this email is still not in "AllContact" section... not sure what I'm missing...thanks for any help!

I am trying add subscribers to all subscribers with import type as add only. But I am getting as duplicate eventhough it is not present in all sub list?

is subscriber id and contact id the same?? ... just like subscriber key and contact key?