This book aims to help IT system administrators and engineers gain a better understanding of E-mail technology.It covers numerous aspects of email architecture, design, implementation and troubleshooting and also the communication protocols, the characteristics of large-scale architecture with other related subjects such as SPAM and legal obligations that should be considered when managing and providing email services.There are detail descriptions of the common email servers along with setup, configuration and troubleshooting instructions. Popular email clients, DNS setup for email, attachments, and common email services are also reviewed and examined. As we proceed through the latter chapters of the book, the misuse of email - spam - is considered with guides to avoid issues and help organizations prevent their emails from being blacklisted.Email security is of paramount importance as there is an abundance of viruses and malware that can compromise data security. Using encryption and digital signing goes some way to securing email and will be examined in detail in the tenth chapter of this book. The final chapter reviews etiquette of email and the hoped is that this book will give valuable insight to all those who seek it.