Spark glossary
Everything you need to understand email—clear, simple definitions from A to Z.
Email overload
Email overload is when incoming volume outpaces your ability to process it. Here's why it happens and the tactical fixes that actually help.
Email fatigue
Email fatigue is the burnout from constantly checking your inbox, not the volume itself. Here's why the habit forms and how to actually break it.
Email anxiety
Email anxiety is the dread of opening your inbox and not knowing what you missed. Here's why it happens and what actually helps.
Inbox zero
Inbox Zero is a specific method for clearing your inbox to empty using five simple actions. Here's how it works and whether it's actually worth adopting.
End-to-end encryption
End-to-end encryption means only the sender and recipient can read an email's contents, not even the provider. Here's how it works and who actually needs it.
Email tracking
Email tracking shows whether and when a recipient opened or clicked your message. Here's how it actually works, and why the data isn't always reliable.
Email template
An email template is a reusable, designed layout for newsletters and outreach, not the same as a quick canned reply. Here's how templates work and how to build one.
Automatic forwarding
Automatic forwarding routes incoming mail to another address without you touching it. Here's how to use it properly, and why attackers abuse it too.
POP3 or Post Office Protocol version 3
POP3 is the older email protocol that downloads messages to one device and often deletes them from the server. Here's how it works and when it's still used.
Out of office
An out of office reply tells senders you're away, but for teams sharing an inbox it's really a coverage problem. Here's how to set one up and get it right.
Email spoofing
Email spoofing fakes the sender's address to make a message look like it came from someone else. Here's how it works and how to protect yourself.
Email service provider
An email service provider hosts and delivers your email, but it's not the same as your email client. Here's the difference, and how to choose one.
Email management
Email management is how you organize, prioritize, and process your inbox so it doesn't run your day. Here's what it actually involves and how to build a system
Email deliverability
Email deliverability determines whether your messages reach the inbox, the spam folder, or nowhere at all. Here's what affects it and how to check yours.
Email filter
An email filter automatically sorts, labels, or hides mail based on rules you set. Here's how filter criteria actually work, and how they differ from spam filters.
Automated Email Reply
An automated email reply is a pre-written message sent automatically in response to incoming email. Learn how auto-replies work and when to use them.
Undisclosed recipients
Undisclosed recipients is an email technique that hides the full list of recipients in a BCC send. Learn when to use it and what it signals to your contacts.
Email storage
Your email storage limit is the maximum data your mailbox can hold. Learn how limits work in Gmail and Outlook, what happens when you hit them, and how to free up space.
Scheduled Send
Scheduled send lets you write an email now and deliver it at any date and time you choose. Learn how it works in Gmail, Outlook, and Spark.
Snooze an email
Snoozing an email removes it from your inbox temporarily and brings it back at a time you choose. Learn how snooze works in Gmail, Outlook, and Spark.
Smart Reply
Smart Reply is an AI feature in Gmail and other email clients that suggests short reply options based on the email you received.
Unsubscribe link
An unsubscribe link lets you opt out of email lists with one click. Learn how they work, what good ones look like, and how to use them in Gmail, Outlook, and Spark.
Primary Email
Primary email is the main inbox tab in Gmail where personal and important messages land. Learn how it works and how to use it more effectively.
Email client
An email client is the app you use to read and send email, like Gmail, Outlook, or Spark. Here's how they work and how to pick the right one.
Dynamic email
Dynamic email lets you take action, like RSVPing or checking a status, right inside a message. Here's how it works and where you'll see it.
Disposable email address
A disposable email address is a temporary inbox you use once and toss. Learn how they work, when to use one, and when they backfire.
CCPA
CCPA gives California residents real control over their personal data, including what's collected through email. Here's what it means for you.
CAN-SPAM Act
The CAN-SPAM Act sets the rules for commercial email in the US. Here's what it requires, who it applies to, and what happens if you ignore it.
SMTP Server
An SMTP server is the system that sends your outgoing emails across the internet. Learn how SMTP servers work, how they differ from IMAP, and what settings you need.
Reverse DNS Lookup
Reverse DNS lookup maps an IP address back to a domain name using PTR records. Learn why it matters for email deliverability and how to check your reverse DNS setup.
DMARC Record
A DMARC record is a DNS policy that tells receiving servers what to do when emails fail authentication checks. Learn how DMARC protects your domain from spoofing.
Custom Email Domain
A custom email domain uses your own domain name instead of @gmail.com. Learn why it matters for credibility and how to set one up for your business or personal brand.
Webmail
Webmail lets you access your email through a browser without installing any software. Learn how webmail works, its pros and cons, and how it compares to email clients.
Newsletter
A newsletter is a recurring email sent to subscribers with updates, content, or offers. Learn how newsletters work and how to manage them as a recipient or sender.
Email account
An email account is your personal address for sending and receiving email. Learn how email accounts work, how to set one up, and how to manage multiple accounts.
Inbox
Your inbox is the central folder where incoming emails land. Learn how it works, how to organize it, and how to stop it from controlling your day.
Whitelist (email)
Email whitelisting (or allowlisting) marks senders as trusted so their emails always reach your inbox. Learn how to whitelist addresses and why it matters.
DKIM
DKIM uses digital signatures to authenticate emails and verify they haven't been tampered with. Learn how DKIM works, why it matters, and common setup questions.
Blacklisting (email)
Email blacklisting blocks senders flagged as spam sources. Learn how blacklists work, why domains get listed, how to check your status, and avoid getting blocked.
Verification email
A verification email confirms email addresses and user actions. Learn how verification emails work, why they matter for security, and best practices for sending them.
Yellowlisting (email)
Yellowlisting temporarily flags email servers that send mostly good mail, but some spam. Learn how it works, why major providers use it, and how to avoid getting yellowlisted.
Unsubscribe
Unsubscribing removes you from email lists you don't want. Learn how unsubscribe links work, why some don't work, and how to unsubscribe in Gmail, Outlook, and Spark.
Trash folder
The trash folder stores deleted emails temporarily before permanent deletion. Learn how long emails stay in trash, how to recover them, and how to empty trash in Gmail, Outlook, and Spark.
Spam filter
Spam filters automatically detect and block unwanted emails. Learn how spam filters work, why legitimate emails sometimes get blocked, and how to improve filtering accuracy.
Spam email
Spam email is unwanted junk mail that clogs your inbox. Learn how spammers operate, why spam filters sometimes fail, and how to reduce spam in Gmail, Outlook, and Spark.
Read receipt
A read receipt confirms when someone opens your email. Learn how read receipts work in Gmail, Outlook, and Spark, plus why they're not always reliable.
Queued email
Queued emails are messages waiting to send due to connectivity issues, server problems, or sending limits. Learn why emails get queued and how to resolve this issue.
Phishing email
Phishing emails impersonate trusted senders to steal passwords and data. Learn how to identify phishing attempts and protect yourself from email scams.
One-click unsubscribe
One-click unsubscribe lets recipients opt out instantly without logging in or filling forms. Learn how it works and why major email providers now require it.
Non-delivery report (NDR)
A non-delivery report (NDR) is an automated email telling you your message couldn't be delivered. Learn common causes and how to fix delivery failures.
Mail merge
Learn what mail merge is and how to use it in Gmail, Outlook, and Excel. Step-by-step guide to creating personalized mass emails with mail merge tools.
Two-factor authentication (2FA)
Two-factor authentication (2FA) adds a second security layer to your email account. Learn how 2FA works, setup steps for Gmail/Outlook, and best practices.
Labels in email
Email labels are tags you apply to messages for organization. Unlike folders, one email can have multiple labels. Learn how labels work and when to use them.
GDPR: The general data protection regulation
GDPR is the EU's data protection regulation governing how you collect, store, and use email addresses. Learn compliance requirements for email marketing and privacy.
HTML email
HTML email uses code to add formatting, images, and links to messages. Learn how HTML emails work, when to use them, and best practices for design and deliverability.
IMAP
IMAP is the protocol that lets you access email from any device while keeping messages synced on the server. Learn how IMAP works and why it beats POP3.
Junk mail folder
The junk mail folder (or spam folder) is where your email client automatically sends suspicious messages. Learn how it works and how to manage it effectively.
AI email writer
An AI email writer is a tool that uses artificial intelligence to generate, edit, and improve emails automatically based on your input.
Email alias
An email alias is an alternate email address that delivers to your main inbox. Learn how to create and manage email aliases in Gmail, Outlook, and other providers.
Alternative email address
An alternative email address is a secondary email you can use alongside your main one—helping you organize messages, protect your primary inbox, or recover your account if needed.
AMP for email
AMP for Email lets you add interactive elements like forms, carousels, and real-time updates directly in messages. Learn how it works and which clients support it.
ARC (Authenticated Received Chain)
ARC (Authenticated Received Chain) preserves email authentication when messages are forwarded or modified. Learn how ARC prevents legitimate emails from failing SPF and DKIM checks.
AOL Mail
AOL Mail is a free webmail service launched in 1993, one of the earliest email platforms. Learn about its features, how it compares to modern clients, and who still uses it.
Analytics for email
Email analytics tracks how people interact with your messages through opens, clicks, bounces, and more. Learn which metrics matter and how to measure email performance.
Archive an email
Email archiving moves messages out of your inbox into long-term storage without deleting them. Learn how to archive emails in Gmail, Outlook, and Spark effectively.
Attachment (email)
Email attachments are files you send with your messages. Learn attachment size limits, security best practices, and how to handle attachments in Gmail, Outlook, and Spark.
Auto-delete
Auto-delete automatically removes old emails after a set period. Learn how to set up auto-delete rules in Gmail, Outlook, and Spark to manage inbox clutter safely.
Auto-fill email address
Auto-fill email address suggests contacts as you type in the "To" field. Learn how auto-fill works in Gmail, Outlook, and Spark, and how to manage suggestions.
Auto-sorting
Auto-sorting automatically organizes incoming emails into folders or labels based on rules. Learn how to set up smart email sorting in Gmail, Outlook, and Spark.
Bulk deleting emails
Bulk deleting lets you delete multiple emails at once instead of one by one. Learn how to mass delete emails in Gmail, Outlook, and Spark to clear inbox clutter quickly.
Canned email
A canned email is a pre-written template you save and reuse for common responses. Learn how to create canned responses in Gmail, Outlook, and Spark to reply faster.
Recover deleted emails
Learn how to recover deleted emails in Gmail, Outlook, and Spark. Most email services keep deleted messages for 30 days before permanent deletion.
Automation (email)
Email automation uses rules and triggers to handle repetitive tasks automatically. Learn how to set up filters, auto-replies, and workflows in Gmail, Outlook, and Spark.
Flagged as spam
When emails are flagged as spam, they go to the spam folder instead of the inbox. Learn why this happens and how to fix spam filtering issues in Gmail, Outlook, and Spark.