Overview
Who this page is for
| Audience | Why it matters to you |
|---|---|
| Everyone | You need these mental models before moving forward |
| Analysts | Understand what data you are and are not collecting |
Analytics Fundamentals
Before diving into props, eVars, and segments, you need to understand four foundational concepts:
The hit model
Every request to Adobe Analytics is a hit — one HTTP request carrying one data payload. A hit is the atomic unit. You cannot have half a hit or 1.5 hits. Each hit either fires or doesn't.
Visit and visitor scoping
All hits get rolled up into visits and visitors. A visitor is a person (identified by ECID or logged-in user ID). A visit is a session — a bounded stretch of activity from the same person. Visits time out after 30 minutes of inactivity by default.
The collection pipeline
Data flows: your site → Adobe Edge → Adobe's data centers → report suite database. This pipeline has many places where data can be lost, modified, or rejected. Understanding this flow helps you debug.
Dimensions vs metrics
A dimension is a grouping axis (what you want to count *by*). A metric is a counter (what you want to count). "Visitors by page" means page is the dimension, visitor count is the metric.
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Reading this section
- Start with Hits, visits and visitors to lock in the scoping model
- Move to The collection pipeline to see where data goes
- Read Dimensions vs metrics to build the mental model for reporting
- Identity, ECID and its limits explains how visitors are identified
- Out-of-the-box variables shows what Adobe gives you for free
- Server calls as a design constraint explains why you cannot collect everything