B

 B-to-B (B2B):
Business to Business.

B-to-C (B2C):
Business to Consumer.

Blacklist or blacklist:
An email list that includes domains or IP addresses of any issuer of suspicious emails to send spam. Many companies use blacklists to reject inbound email, either at the server level or before it reaches the recipient in the tray. Also blocked list.

Block: 
An action for an ISP to forward messages from a mail sender to the recipient. This is an activity other than a bounce.

Bonded Sender:
A certain type of delivery that provide some private companies to secure approval for email marketing companies.

Bounce e-mail:
An e-mail is not delivered normally said to have been bounced. The emails can be bounced for many reasons, incorrect email address, the recipient's mailbox is full, the mail server is down, or the system detects it as spam or offensive content.

Bounce message:
Message sent back to a mail address to which the reporting message could not be delivered. Not all bounced emails are sent back to the sender.

Bounce handling:
The process of dealing with email that has been recovered. Bounce handling is important for list maintenance, list integrity and delivery. Given the lack of consistency in bounce messaging, managing list software is programmed with various rules and needs manual when you can not determine the nature of the dismissal.

Bounce rate:
Percentage of hard / soft boot in relation to total emails sent. Always a relative proportion, as some systems do not clearly inform the sender.

Broadcast: 
The process of sending the same message to multiple recipients.