# Glossary

> Definitions of the key terms used throughout Ordinary.

Source: https://help.tryordinary.com/reference/glossary

---

## ACoS
**Advertising Cost of Sales.** Ad spend divided by ad-attributed
sales. Amazon's primary efficiency metric. ACoS of 25% means you
spent $0.25 on ads for every $1 of attributed sales. Lower is better
(inverse of ROAS).

## Attribution
Assigning credit for a conversion (order) to a specific channel or
campaign based on the customer's journey. Different **attribution
models** distribute the credit differently — see [Attribution models explained](https://help.tryordinary.com/concepts/attribution-models).

## AOV
**Average Order Value.** Total revenue divided by order count.

## CAC
**Customer Acquisition Cost.** Ad spend divided by new customers
acquired. Used in the [Offer calculator](https://help.tryordinary.com/features/offer-calculator)
to evaluate whether a discount is justified.

## Channel
High-level bucket for where a session came from: Email, Paid Social,
Organic Search, Direct, etc. Derived from UTM parameters via the
[channel taxonomy](https://help.tryordinary.com/concepts/channel-taxonomy).

## Client ID
An anonymous, stable identifier for a browser. Set by Ordinary's
first-party pixel. Used to stitch sessions together across
pageviews.

## Cohort
A group of customers who share a common start date (usually the
month of first order). [Cohort retention analysis](https://help.tryordinary.com/features/cohort-retention)
tracks how each cohort's retention curve evolves.

## CTR
**Click-Through Rate.** Clicks divided by impressions. Delivery-level
metric, same definition Meta / Google / Amazon use.

## First-click attribution
An attribution model that gives 100% of the credit for an order to
the very first session where the customer arrived. Good for measuring
acquisition channels.

## First-party pixel
A tracking script that runs on your own domain instead of a
third-party ad platform's. Survives ad blockers and iOS privacy
rules better than traditional Facebook Pixel / Google Tag. See
[What is a first-party pixel?](https://help.tryordinary.com/concepts/first-party-pixel).

## Funnel
The sessions → product views → add-to-cart → checkout → order
progression. Shows drop-off rates at each step. See [Funnel](https://help.tryordinary.com/features/funnel).

## GMV
**Gross Merchandise Value.** Total Shopify sales in the last 12
months. Used to determine pricing tier. See [Understanding your GMV tier](https://help.tryordinary.com/concepts/gmv-tiers).

## Last-click attribution
An attribution model that gives 100% of the credit for an order to
the final session before the customer converted. Default in
Ordinary, Shopify, and Google Analytics 4. Good for measuring
bottom-of-funnel performance.

## Linear attribution
An attribution model that distributes credit equally across every
session in the customer's journey. Good middle ground when you
don't want to overweight either end. Available on Starter+.

## Lookback window
How far back in time a report can pull data. Plan-dependent:

- Free: 30 days.
- Starter: 12 months.
- Advanced: 24 months.
- Enterprise: unlimited.

## Merchant
A Shopify store using Ordinary. Synonym with "customer" when talking
about Ordinary's own business, but in the app UI we say "store" or
"organization" to avoid confusion with a merchant's end customers.

## Organization
The Ordinary account that contains one Shopify store, its
integrations, and its team members. Usually 1:1 with a merchant.

## Over-tier
When your Shopify 12-month GMV exceeds the cap for your current
plan tier. Triggers a warning banner at first; keeps escalating
if GMV stays well past the cap. See
[Over-tier banner](https://help.tryordinary.com/billing/over-tier-banner).

## Pixel
Shorthand for Ordinary's first-party tracking script installed via
Shopify's Customer Events extension. See
[Customer Events pixel extension](https://help.tryordinary.com/integrations/customer-events-pixel).

## ROAS
**Return on Ad Spend.** Attributed revenue divided by ad spend.
Inverse of ACoS. ROAS of 4 means you got $4 in attributed revenue
per $1 of ad spend.

## Session
A period of continuous activity from a single browser on your
storefront. Starts on first pageview, ends after 30 minutes of
inactivity or at midnight UTC.

## Subscription-aware attribution
Separating first-time orders from recurring subscription reorders
in attribution calculations. Keeps retention billing out of your
acquisition ROAS.

## Time-decay attribution
An attribution model that weights recent sessions more heavily than
earlier ones in the customer's journey. Available on Starter+.

## UTM parameters
Query string tags (`utm_source`, `utm_medium`, `utm_campaign`, etc.)
that travel with a link and tell analytics tools where the visitor
came from. Ordinary uses UTMs to classify sessions into channels.

## Webhook
A real-time HTTP POST from Shopify to Ordinary when something
changes (order placed, customer created, etc.). Most Shopify data
flows through webhooks rather than polling.