Email is the most important messaging system of the Internet – the one that carries vital information. While we all like to chat on our smartphones and exchange updates on social networks, it is usually our email that delivers bills, contracts, account registrations and passwords, health information, e-commerce orders, flight tickets and all other sorts of important documents.

Keeping email secure is a priority for all those who build and use the Internet, be them average consumers, system administrators, or Internet service providers.

In this introductory section we provide simple, easy to understand summaries about the most common threats to the security of email, and about the most common practices and technologies to address them. You will then find specific information on what you can do to secure your email in the remaining sections of the website, depending on whether you are an ISP, a sysadmin or a user.

Read about key email security threats: spam, phishing and malware, mailbox cracking, email interception.

Read about technologies that can counter them: SPF, DKIM, DMARC, TLS/SSL, STARTTLS, DNSSEC, DANE.