Knowledge Base

Cross-domain tracking connects a visitor's activity across related domains, such as a storefront and a separate checkout.

The GA4 Measurement Protocol sends events directly to Google Analytics through HTTP requests, usually from a server or an offline system.

transaction_id is the parameter on a GA4 purchase event that identifies the order the event belongs to.

Unassigned is a default channel group in GA4's traffic acquisition reports that captures sessions GA4 could not match to any defined channel rule — such as Direct, Organic Search, or Paid Social — because the session lacked the source, medium, or campaign data those rules require.

The dataLayer is a JavaScript array that a website pushes structured event data into, acting as a message queue between the site's code and a tag management system such as Google Tag Manager.

First-party tracking means setting tracking cookies and sending tracking requests from the same domain the visitor is on, rather than from a third-party domain such as a vendor's own servers.

A server container is a Google Tag Manager container that runs on a server you or a managed service control, rather than in the visitor's browser, and receives events forwarded to it from a web container or sent directly via HTTP.

An attribution window is the period after an ad interaction during which a conversion can still be credited to that interaction.

Click IDs are platform-provided references carried in a landing URL after an ad interaction.

Event Match Quality (EMQ) indicates how effectively the customer information sent with a server event may match it to Meta accounts.

event_id is a unique identifier attached to both the browser-side (Pixel) and server-side (Conversions API) copies of the same conversion event, such as a purchase.

The Meta Conversions API (CAPI) is Meta's server-to-server interface for sending conversion events from a website, app, CRM, or offline source directly to Meta rather than through the browser Pixel.

Offline conversion import sends a later business outcome, such as a qualified lead or a completed sale recorded in a CRM, to Google Ads.

Consent Mode v2 is Google's framework for signaling a website visitor's cookie consent status to Google tags — Google Ads, Google Analytics, Floodlight — so those tags adjust their behavior instead of firing unconditionally.

Cookieless pings are the requests Google tags send to Google when a visitor has denied storage consent under advanced Consent Mode.

Order reconciliation is the process of matching individual orders recorded in a commerce platform's backend, such as Shopify or a payment processor, against the same orders as reported by analytics and ad platforms such as GA4 or Meta Ads, using the backend as the source of truth.

Checkout extensibility is Shopify's app-and-extension model for customizing checkout, Thank you, and Order status pages, replacing the theme-based checkout.liquid template and Additional Scripts.

Shopify Customer Events are the standardized behavioral events — such as product_viewed, product_added_to_cart, and checkout_completed — that a Shopify store publishes to its own data layer, which web pixels subscribe to and forward to analytics or marketing endpoints.