21 terms
Email security terms
From spoofing to encryption, email security terms explain the tools and threats that affect your inbox. Whether you're reading, sending, or filtering emails, this vocabulary helps you protect what matters.
Spam and Open Relay Blocking System
The spam and open relay blocking system (SORBS) is a service that identifies and stores IP addresses known for sending spam.
Spamming
Spamming refers to the act of sending unsolicited messages, often excessively, about a product or service.
Snowshoe spam
Snowshoe spam is a technique designed to distribute spam emails across a broad range of IP addresses and domains.
SMTP proxy
An SMTP proxy is a type of proxy via which you get a basic level of control over your incoming email messages.
SMIME
SMIME is a standard for digitally signing and encrypting email messages.
Self-destructing email
A self-destructing email is an email that is designed to disappear or become inaccessible after a certain period of time or after it has been read by the recipient.
Relay server
A relay server is a service that simplifies the process of sending emails to several recipients for the user.
Open relay
An open relay allows any sender to transmit email through a mail server without requiring authentication.
Multi-Purpose Internet Mail Extensions
Multi-Purpose Internet Mail Extensions (MIME) is a fundamental email standard that allows users to send files (e.g., videos, photos, or audio recordings) over email.
Greylist
A greylist is a list that contains temporarily rejected email addresses.
Graymail
Graymail refers to promotional or subscription-based emails like newsletters, promotional offers, or announcements.
Email signature
An email signature is a block of text at the end of an email message with information about the sender.
Email retention policy
An email retention policy is a formal framework of guidelines and regulations that governs email storage, archival, and deletion.
Email harvesting
Email harvesting involves gathering email addresses from various sources without permission.
Email gateway
An email gateway is a method used to protect an organization’s or individual’s email servers.
Drop address
A drop address is a location where someone receives goods or packages anonymously, without being linked to the person who dropped them off.
DomainKeys Identified Mail
DomainKeys Identified Mail, commonly known as DKIM, is an email authentication method to detect email spoofing.
Bounced email
Bounced emails are emails that failed to reach the recipient's inbox and return to you with a notification of their failure.
Bayesian filter
The Bayesian filter is a method that uses Bayesian statistics to predict the likelihood of events, like figuring out if an email is spam.
Anti-spam
Anti-spam is any software, hardware, or technique to protect devices and accounts from spam — the mass sending of unsolicited messages.
Anti-phishing service
An anti-phishing service is a specialized cybersecurity solution against phishing and certain other forms of social engineering attempts.
The importance of email security terminology
Email is one of the most common targets for cyberattacks. Understanding the terms behind email security helps you spot red flags and stay protected from scams.
Avoid phishing traps
Knowing terms like “spear phishing” or “email spoofing” makes it easier to recognize suspicious messages before they trick you.
Keep sensitive info private
Terms like “end-to-end encryption” explain how your emails can be secured from prying eyes — including your provider.
Reduce the risk of account takeovers
Email is often the gateway to your entire digital life. Understanding how attacks happen helps you shut the door on intruders.
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