Glossary
The terms, honestly explained
The messaging world loves acronyms. Here they all are — what they mean, why they exist, and where in the platform they're used.
- A/B test
- Splitting an audience to compare two versions — subject lines, content, send times — and measure which performs better. In WeZend, A/B arms live inside campaigns and journeys alongside holdout groups.Read more in the docs
- Behavioural event
- A recorded customer action — page viewed, product added to cart, order completed — with properties and a timestamp. Events are the raw material of the CDP: they build profiles, update segments and trigger journeys.Read more in the docs
- BIMI (Brand Indicators for Message Identification)
- A standard that shows your verified logo next to your emails in supporting inboxes. It requires DMARC enforcement first, and it lifts trust and open intent by making your mail visibly, verifiably yours.
- CDP (Customer Data Platform)
- A system that merges customer data from every source — website, shop, backend, messages — into one profile per human, in real time. In WeZend the CDP isn't a separate product: every send, segment and journey reads from the same profile the events write to.Read more in the docs
- Churn risk
- A predictive signal that a customer is likely to lapse or cancel, based on their behaviour trend. Segment on it to trigger a win-back before they leave — cheaper than winning them back after.Read more in the docs
- Computed trait
- A value calculated from a contact's history and stored on the profile — total orders, days since last click, average basket. Defined once, updated continuously, segmentable like any field.Read more in the docs
- CPaaS (Communications Platform as a Service)
- API infrastructure for sending and receiving messages — SMS, voice, WhatsApp — without owning carrier connections yourself. WeZend is a CPaaS with a CDP underneath, which is the difference between sending messages and sending the right ones.Read more in the docs
- Dead-letter queue
- Where messages that failed all delivery attempts wait for inspection and manual retry — instead of vanishing. Nothing on WeZend fails silently; that's the point.Read more in the docs
- Deliverability
- The share of your messages that actually reach the inbox (not the spam folder, not silently dropped). Built from domain authentication, list hygiene, engagement and complaint rates — it compounds over months and can be destroyed in a week of careless sending.Read more in the docs
- DKIM (DomainKeys Identified Mail)
- A cryptographic signature added to every email, verifiable against a public key in your DNS. It proves the message really came from your domain and wasn't altered in transit. WeZend signs automatically once your domain is verified.Read more in the docs
- DLR (Delivery Receipt)
- The carrier's confirmation that an SMS reached the handset. 'Sent' means handed to the operator; 'delivered' means a DLR came back. WeZend surfaces the difference honestly — and flags messages stuck between the two states.Read more in the docs
- DMARC
- A DNS policy telling receivers what to do with mail that fails SPF/DKIM (deliver, quarantine or reject) and where to send reports. Gmail and Yahoo require it for bulk senders — it's not optional at volume anymore.Read more in the docs
- Domain warm-up
- Gradually increasing send volume on a new sending domain so mailbox providers learn to trust it. Blasting a cold domain teaches them you're a spam source; ramping over two to four weeks builds reputation instead.Read more in the docs
- Double opt-in
- A signup only counts after the subscriber clicks a confirmation link. You lose the fake and mistyped addresses — deliberately, because those addresses were future bounces and spam traps. The GDPR gold standard and the cheapest deliverability insurance there is.Read more in the docs
- E.164
- The international phone number format: plus sign, country code, number, no spaces — +4512345678. The only format APIs should ever exchange; everything else is a guess about the sender's country.Read more in the docs
- Engagement score
- A computed measure of how actively a contact opens, clicks and interacts. WeZend derives it on the profile so you can segment on "highly engaged" or "cooling off" without maintaining the math yourself.
- Frequency cap
- A platform-level limit on marketing pressure — e.g. max 4 marketing messages per contact per week, across all channels and all sources. However many campaigns target a contact, the cap decides what actually goes out.Read more in the docs
- GSM-7 / UCS-2
- The two SMS encodings. GSM-7 covers basic Latin characters (160 per segment); UCS-2 covers everything else — emojis, most non-Latin scripts — at 70 characters per segment. The encoding is decided by the single 'worst' character in your message.Try the segment calculator
- Hard bounce
- A permanent delivery failure — the address doesn't exist or rejects you outright. Keep sending to hard-bounced addresses and mailbox providers punish your reputation; WeZend suppresses them automatically.Read more in the docs
- Holdout group
- A random slice of a campaign audience that deliberately receives nothing. If the messaged group converts at 4.1% and the holdout at 3.9%, your campaign earned 0.2 points — not 4.1. The only honest way to measure uplift.Read more in the docs
- Inbox placement
- Whether your email lands in the primary inbox, a tab, or the spam folder — distinct from mere delivery. Seed-inbox testing before a big send catches placement problems on a test list, not your whole audience.Read more in the docs
- Incrementality
- The extra revenue a campaign actually caused — versus revenue that would have happened anyway. You measure it with a holdout group that receives nothing; the difference is the true lift, the only number worth scaling on.Read more in the docs
- Journey
- An automated flow on a visual canvas that reacts to individual behaviour over time: trigger → delay → branch → send, across all six channels, with frequency caps and quiet hours enforced and a goal that attributes revenue.Read more in the docs
- List hygiene
- The ongoing practice of keeping your contact list clean — removing bounces, suppressing unengaged addresses, honouring opt-outs. Good hygiene is the cheapest deliverability insurance there is.
- llms.txt
- A convention (llmstxt.org) for publishing a machine-readable map of your site for AI assistants. WeZend serves both /llms.txt (the map) and /llms-full.txt (the entire documentation as one file) — so an AI assistant can integrate the platform without browsing.Read more in the docs
- MCP (Model Context Protocol)
- An open standard that lets an AI assistant call external tools. WeZend exposes an MCP server so Claude, ChatGPT or another assistant can read, configure and (with confirmation) operate your account in plain language.Read more in the docs
- One-click unsubscribe (RFC 8058)
- A machine-readable unsubscribe header that lets mail clients offer an instant opt-out button. Required by Gmail and Yahoo for bulk senders; WeZend adds it to every marketing email automatically.Read more in the docs
- OTP (One-Time Password)
- A single-use code sent by SMS, email or another channel to verify identity at login or checkout. Speed and reliability matter most; WeZend routes OTPs for fast delivery and tracks per-message status.
- Predicted CLV / LTV
- An estimate of a customer's future lifetime value from their history and behaviour. Use it to prioritise VIP treatment, size acquisition budgets, and decide who's worth a win-back incentive.Read more in the docs
- Quiet hours
- A nightly window where marketing messages are held and queued rather than sent — in the contact's own timezone when known. Transactional traffic (OTPs, receipts) is exempt by design: a 3 a.m. login code must arrive at 3 a.m.Read more in the docs
- RCS (Rich Communication Services)
- The successor to SMS: verified sender branding, images and carousels, tappable buttons, and read receipts — in the phone's native messaging app. WeZend sends RCS with automatic SMS fallback for devices that can't receive it.Read more in the docs
- Reverse ETL / audience activation
- Pushing segments OUT of your customer platform into ad networks — Meta, Google, TikTok — as hashed audiences for targeting and lookalikes. PII is SHA-256-hashed locally before anything leaves the platform.Read more in the docs
- Segment
- A live audience rule, not a snapshot: 'spent over €500 AND inactive 30 days'. Contacts flow in and out automatically as their data changes, so campaigns and journeys always hit the current members. Static groups are called lists.Read more in the docs
- Send-time optimization
- Scheduling each contact's message for the hour they personally tend to engage, derived from their event history — rather than one blast time for the whole list. Same message, delivered when people are actually looking.Read more in the docs
- Sender ID
- The name or number an SMS appears to come from. Every country regulates them differently — some allow any alphanumeric name, some require operator registration, some force numeric senders. Getting it wrong means paid-for messages that never arrive.Read more in the docs
- SMS segment
- The billing unit of SMS. One segment is 160 characters with the GSM-7 alphabet — but a single emoji or special character switches the whole message to Unicode, cutting segments to 70 characters. Long messages are split and billed per segment.Try the segment calculator
- Soft bounce
- A temporary delivery failure — a full mailbox, a server hiccup. WeZend retries these, but a repeated soft bounce eventually behaves like a hard bounce and gets suppressed to protect your sending reputation.
- Spam trap
- An email address that exists only to catch senders with poor list hygiene — no human reads it, so any mail to it signals you're emailing addresses you shouldn't. Hitting traps damages reputation fast; good acquisition and suppression avoid them.Read more in the docs
- SPF (Sender Policy Framework)
- A DNS record listing which servers are allowed to send email for your domain. One of the three records (with DKIM and DMARC) that inbox providers check before trusting your mail.Read more in the docs
- Suppression list
- The registry of addresses and numbers you must never message: unsubscribes, hard bounces, complainers. WeZend enforces it at send time across every campaign, journey and API call — and importing your old provider's suppressions is step one of every migration.Read more in the docs
- Transactional vs. marketing
- Transactional messages (OTPs, receipts, delivery notices) are triggered by the recipient's own action and bypass consent requirements, frequency caps and quiet hours. Marketing messages require consent and respect every guard rail. The flag is set per send.Read more in the docs
- Unified profile
- A single record per real person that merges their identity, contact points, traits and event history across channels. Every WeZend send and segment reads from it, so there's one source of truth about each customer.Read more in the docs
- VAPID
- The open standard behind web push: your server proves its identity to browser push services with a key pair — no app store, no Google/Apple account required for the web. WeZend's one-script SDK handles it.Read more in the docs
- Warehouse sync
- Continuous export of profiles and events to your own database or data warehouse. Your BI team queries customer data where they already work — and your data is never locked in.Read more in the docs
- Webhook
- An HTTP callback: instead of you polling for status, the platform POSTs to your URL the moment something happens — delivered, failed, clicked, replied. Every WeZend webhook is HMAC-signed so you can verify it's really from us.Read more in the docs
- WhatsApp 24-hour session
- Meta's rule: free-form messages are only allowed within 24 hours of the customer's last message to you. Outside the window you must use a pre-approved template. WeZend enforces this automatically so sends never bounce off the rule.Read more in the docs
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