A header email is the introductory section of an electronic message, typically displayed at the top of the email. It includes the sender’s name, email address, subject line, and date and time of sending. The header email serves as a brief summary of the message and allows the recipient to quickly identify and organize their emails. It also provides important information for email clients to properly route and deliver the message. In some cases, the header email may also contain additional details such as the recipient’s name and email address, as well as any CC or BCC recipients. Overall, the header email plays a crucial role in effective communication and efficient email management.