---
slug: glossar
title: "Glossary: the key terms"
category: grundlagen
locale: en
updated: 2026-10-17
keywords: ["glossary","terms","definition","touchpoint","journey","credit","ROAS","impression","viewability"]
questions: ["What do the terms Metrunio uses mean?","What is a touchpoint?","What is a credit?","Terms explained","What is a write key?","What is ROAS?","What is the difference between an impression and viewability?","What is a contribution margin?","What is CPA?","What does “Direct” mean?","What is a cohort?","What is a DPA?","What is a session?"]
url: https://bench.metrunio.com/en/help/glossar
---

# Glossary: the key terms

**What do the terms Metrunio uses mean?**

The terms are deliberately narrow: a touchpoint is a measured contact, a journey a chain of such contacts, a credit an attributed share. This list explains the terms used in the portal and in reports.

| Term | Meaning |
| --- | --- |
| Site | A website or app with its own site ID and keys. |
| Site ID | Public identifier of a site; appears in the tracking code. |
| Write key | Key that lets the browser send events. Publicly visible, bound to domains. |
| Server key | Key for server-side events. Secret, never in the browser. |
| Event | A stored occurrence with timestamp and event type. For billing, the counting rule on the pricing page applies: four served impressions are one event. |
| Touchpoint | An advertising or website contact inside a journey. A visit is one touchpoint, not every page view in it. |
| Journey | The measured contacts and visits of one identity on the way to an order or lead, in chronological order. |
| Visit (session) | A connected sequence of page views. A new visit starts after a 30-minute pause or with a new campaign signal. Measured only with consent to analytics, which is one reason the number differs from the sessions in other tools. |
| Identity | Pseudonymous grouping of related identifiers within one tenant. |
| Conversion | The goal you defined: an order, a lead, a completed step. What is measured is that it was reached. |
| Attribution | A rule, the model, distributes a conversion’s revenue across the measured touchpoints before it. It describes an assignment, not an effect. |
| Credit | The share of a conversion a model assigns to a touchpoint. |
| ROAS | How much attributed revenue comes per euro of ad spend. It is not profit. |
| Contribution margin | Net revenue minus cost of goods, both after refunds. Only across orders that carry both figures. |
| Margin ROAS | Attributed contribution margin divided by ad spend. Based on what is left, not on revenue. Below 1, the contribution margin does not cover the ad spend. |
| CPA | Ad spend divided by attributed conversions, meaning what one conversion cost on average. A conversion can also come from a returning customer. |
| New-customer cost (CAC) | Ad spend divided by attributed orders from new customers. What a new customer cost, not what an order cost. |
| Cohort | All customers whose first purchase fell in the same month. “Commerce & products” shows what they are worth in the months after. |
| Acquisition value | What a conversion without an amount of its own is worth to you, set in the portal. Not revenue. |
| Impression | An ad was served. It says nothing about whether anyone saw it. |
| Viewability | The ad was in view for as long and as large as the threshold requires (50 per cent of its area, one second). It says nothing about whether anyone looked. |
| Post-view | A viewable ad that was not clicked is linked to a later conversion and taken into account by the model. That only works where your own tag runs and the browser returns the view identifier. |
| Click window | Period in which a click before the conversion still counts. |
| View window | Period in which a viewable impression still counts. |
| Direct | Channel for visits without a recognisable origin: no click ID, no UTM details, no referrer. It can be large because clicks from apps, PDF documents, bookmarks and pages with a strict referrer policy end up here. “Direct” means “we do not know where from”, not “someone typed the address”. |
| Referral | Channel for visits through a link on another website that matches no other channel. The report shows the website by its host name. |
| Programmatic | Ads bought automatically through a demand-side platform (DSP) on other websites. They are measured like display, with your own tracking elements. |
| Tenant | A separate customer account; for an agency, the account of a client company. Data ends at that boundary. |
| DPA | The data processing agreement under Art. 28 GDPR between your company and Metrunio. Without it, Metrunio accepts nothing. |
| Consent tool (CMP) | The tool behind your cookie banner that asks for consent and stores it, such as Usercentrics or Cookiebot. Metrunio reads the decision from it. |
| Tracking element | Generated pixel, viewability tag or click URL for a creative. |
| Impression ID | Identifier of a single delivery; links pixel, viewability and click. |
| Test data | Events with environment test; excluded from standard reports. |
| Measured | Metrunio recorded it itself. |
| Attributed | A model distributed it. |
| Set | You decided the value yourself, such as the acquisition value. It is not revenue. |
| Self-reported | A customer said it themselves, for example in the post-purchase question. Only the fact that they answered is measured. |
| Reported | The ad platform says it about itself. |

## Also asked

- What is a touchpoint?
- What is a credit?
- Terms explained
- What is a write key?
- What is ROAS?
- What is the difference between an impression and viewability?
- What is a contribution margin?
- What is CPA?
- What does “Direct” mean?
- What is a cohort?
- What is a DPA?
- What is a session?

## Related

- https://bench.metrunio.com/en/help/gemessen-zugeordnet-geschaetzt
- https://bench.metrunio.com/en/help/was-ist-ein-kontakt
- https://bench.metrunio.com/en/help/welche-kennungen
- https://bench.metrunio.com/en/help/post-view-verstehen