Spam is any unsolicited message sent in bulk to people who never asked to receive it. Email is the classic channel, but spam also arrives by SMS, phone call, messaging apps, and social media comments. Three things make a message spam: you never consented to it, it went out at scale rather than to you personally, and it serves the sender's interests, whether that means advertising, fraud, or malware. This guide covers where the word comes from, the types you'll actually run into in 2026, how to protect yourself, and how to keep your own marketing out of the junk folder.
What Exactly Counts as Spam?
A promotional email from a store you subscribed to is not spam. The sender is identified, you consented, and you can unsubscribe whenever you like. A message becomes spam when it fails the consent test. The classic markers:
- No permission: you never gave the sender your contact details, or you gave them for a different purpose (delivery updates, say) and they were reused for marketing.
- Bulk sending: the same message goes to thousands of recipients, often from purchased or scraped lists.
- Hidden or fake identity: spoofed sender names, disposable domains, no physical address, no working unsubscribe option.
- A payload that benefits the sender: pushy sales pitches, phishing links, malware attachments, outright scams.
Most spam is not even criminal. It is just lazy marketing sent without permission. The dangerous part is the overlap with phishing and fraud, which is why mailbox providers and mobile carriers spend so much on filtering it.
Why Is It Called "Spam"?
The name comes from a 1970 Monty Python sketch set in a café where nearly every menu item contains SPAM, the canned meat, and a group of Vikings drowns out all conversation by chanting "Spam, Spam, Spam". Early internet users adopted the term for messages that flooded discussion groups and drowned out real conversation, and it stuck. The message widely cited as the first email spam went out in 1978 over ARPANET, advertising computer equipment to a few hundred recipients at once.
The Main Types of Spam
1. Email spam
Still the highest-volume channel by far. Think unwanted newsletters, shady promotions, phishing emails dressed up as banks or delivery companies, and attachments carrying malware. Filters at Gmail, Outlook, and Yahoo catch the vast majority, so spammers constantly rotate domains, spoof sender names, and copy legitimate branding to slip through.
2. SMS spam (smishing)
Unsolicited text messages pushing loans, gambling sites, fake job offers, and bogus parcel notifications. When an SMS tries to steal credentials or payment details through a link, it is called smishing (SMS phishing). Criminals like this channel for a simple reason: almost everyone opens their texts.
3. Spam and scam calls
Robocalls, aggressive telemarketing, and organized call-center scams impersonating police, banks, customs, or courier companies to pressure victims into transferring money or revealing one-time passwords. Thailand and Southeast Asia have been hit especially hard in recent years, and for consumers this is the most financially damaging form of spam there is.
4. Social media, messaging, and comment spam
Fake accounts mass-sending direct messages, bots dropping links under popular posts, fake giveaway pages, and unsolicited group invitations on Facebook, Instagram, LINE, and WhatsApp. Comment spam on blogs and forums (generic praise plus a link) exists mostly to plant backlinks or lure clicks.
5. SEO spam and link spam
Spam aimed at search engines rather than people: networks of low-quality sites built only to host links, paid link schemes, hacked websites injected with hidden pages, keyword-stuffed doorway pages, and automated comment or forum links. Google's spam policies treat all of these as link spam, and its systems are built to detect and neutralize them.
| Type | Typical examples | Main red flags |
|---|---|---|
| Email spam | Fake invoices, phishing, unwanted promotions | Unknown sender, mismatched domain, urgent tone |
| SMS spam | Loan offers, gambling links, fake delivery notices | Shortened links, requests for OTP or personal data |
| Spam calls | Robocalls, call-center scams, impersonation | Pressure, threats, requests to transfer money |
| Social/comment spam | Bot DMs, fake giveaways, link-drop comments | New accounts, too-good offers, off-topic links |
| SEO/link spam | Paid link schemes, PBNs, hacked-site links | Irrelevant sites linking to you at scale |
Spam vs. Phishing: What Is the Difference?
Spam describes how a message was sent: unsolicited and in bulk. Phishing describes what the message is trying to do: trick you into revealing passwords, card numbers, or one-time passwords by impersonating an organization you trust. A discount email you never signed up for is spam, and mildly annoying. A fake bank email asking you to "verify your account" is phishing, and the right response is different too. Spam you filter and ignore; phishing you should report to your mailbox provider and to the organization being impersonated.
How to Protect Yourself from Spam
How to stop spam emails
- Use the "Report spam" button, not just delete. Every report trains your provider's filter and reduces what reaches you next time.
- Unsubscribe only from senders you recognize. Legitimate unsubscribe links work. For true spam, clicking any link (yes, even "unsubscribe") confirms your address is active. Report those instead.
- Never expose your main address publicly. Posted addresses get scraped. Use a secondary address or aliases for sign-ups, contests, and downloads.
- Check the actual sender domain before clicking anything. Display names are trivial to fake; the domain after the @ is not.
- Turn on two-factor authentication on your email account itself. A compromised mailbox becomes a spam cannon aimed at your contacts.
Blocking SMS and call spam
- Block and report numbers directly in your phone's messaging and call apps; iOS and Android both filter unknown senders.
- Use a caller-ID app such as Whoscall, which most people in Thailand already know, to flag scam numbers before you answer.
- Never share an OTP with a caller, whoever they claim to be. Banks and government agencies do not ask for OTPs by phone. Ever.
- Ask your carrier to opt you out of promotional SMS, and treat any parcel-notification link as hostile until proven otherwise.
Watch for brand impersonation
Scammers increasingly impersonate reputable companies with fake job offers, invoices, and partnership proposals. We know this one first-hand: fraudsters have sent emails pretending to be Relevant Audience, which is why we published an official notice about fraudulent emails using our brand. If an offer feels off, verify through the company's official website, never through the contact details in the message itself.
How Businesses Can Avoid Being Marked as Spam
Mailbox providers do not care about your intentions. If your emails behave like spam (purchased lists, unengaged recipients, missing authentication), they get filtered like spam, and legitimate messages to real customers die in the junk folder alongside them. The fix is unglamorous: three disciplines, done consistently.
1. Permission marketing, always
Only email people who explicitly opted in, and make it effortless to opt out. Never buy contact lists. Most of the deliverability messes we get called in to fix trace back to a list someone bought years earlier: they are full of spam traps and people who will hit "Report spam" on sight. In Thailand this is also a legal question, because the PDPA requires a lawful basis, typically consent, for direct marketing, with fines that can reach millions of baht. Double opt-in keeps your list clean from day one.
2. Email authentication and sender requirements
Since 2024, Gmail and Yahoo enforce strict bulk-sender requirements, and Microsoft has followed for Outlook. Every business sending marketing email in 2026 needs SPF, DKIM, and DMARC on its sending domain, one-click unsubscribe in every bulk message, and a spam complaint rate below 0.3 percent, ideally under 0.1. Miss these and your mail can be rejected outright, no matter how good the content is.
3. List hygiene and engagement
Regularly remove addresses that never open, send at a consistent cadence from a consistent sender name, and warm up new sending domains gradually. Filters judge you on engagement. Mail that people open and reply to earns inbox placement; mail that gets ignored gets buried. If you are not sure your campaigns even reach the inbox, our email marketing service covers authentication setup, list strategy, and campaign management end to end.
How Spam Hurts Your SEO
Spam can also quietly sabotage your search rankings. Google's spam policies target link schemes, and its systems devalue manipulative links continuously, not just during big updates. Three risks worth taking seriously:
- Bought backlinks backfire. Cheap link packages, private blog networks, and mass directory submissions are exactly what Google's systems are trained to detect. At best the links get ignored and the money is wasted; at worst the site picks up a manual action that suppresses rankings until it is cleaned up.
- Spam can target you. Hacked pages injected into your site, spammy user-generated content, and negative-SEO link blasts all associate your domain with spam signals. Regular technical audits and moderated user content are the defense.
- Recovery is slow. Rebuilding trust after a spam penalty takes far longer than earning rankings honestly would have in the first place.
The durable alternative is boring, and it works: quality content, clean site architecture, and links earned on merit. If your site has a history of questionable link building, or you suspect toxic links are pointing at you right now, our SEO service in Thailand includes backlink audits and recovery strategy alongside ongoing optimization.
Frequently Asked Questions
What is spam in simple terms?
Spam is any message you never asked for, sent in bulk to many people at once, usually by email, SMS, phone, or social media. Some of it is merely annoying advertising; some of it is phishing built to steal from you. The key test is consent: if you never gave the sender permission to contact you, and the same message went to thousands of others, it is spam.
Why is junk email called spam?
It comes from a 1970 Monty Python sketch in which the word "Spam" (the canned meat) is repeated so relentlessly it drowns out everything else. Early internet users borrowed it for bulk messages flooding online discussions, and the name stuck.
How do I stop spam emails permanently?
You cannot eliminate spam completely, but you can cut it dramatically: report spam instead of just deleting it, unsubscribe from legitimate senders you no longer want, keep your address off public websites, use aliases for sign-ups, and enable your provider's strongest filtering. Reporting consistently is the habit that pays off most, because it trains the filter on your own mail.
Why do my company's emails go to spam?
The usual causes: missing SPF, DKIM, or DMARC, purchased or stale lists, high complaint or bounce rates, and low engagement. Fix authentication first, remove unengaged contacts, make unsubscribing effortless, and send only to people who opted in. Reputation recovers gradually as positive engagement accumulates.
