Sessions and Visitors
Understand events, sessions, visitor identity, and engagement in Hardal.
An event is an action. A session groups activity during a visit. A visitor identifier can connect recognized activity across visits. These counts answer different questions.
The identifiers
| Concept | Purpose and example |
|---|---|
| Event | An occurrence with a name, time, and parameters, such as one purchase. |
| Session ID | Groups events within a visit, such as a product view, cart action, and purchase. |
| Visitor ID | Identifies recognized visitor activity within the supported collection context, including return visits. |
| User ID | Your stable account or customer ID, supplied through identify or an event payload. |
A session ID is not a customer ID. Do not use one fixed session ID for every user, or generate a new session ID for every event.
The web tracker manages session grouping. For mobile and backend requests, provide a stable session UUID when events belong to the same session. Without one, the collection service creates a session ID; separate requests are not guaranteed to describe one visit. See Mobile Setup and API & Server-side Setup.
Anonymous and recognized activity
Hardal can group anonymous events into sessions without a visitor identity. Without granted consent or a valid matching identity cache, the collection service removes userId and visitorId before processing. Explicit denial clears the identity cookie.
When identity processing is allowed, supplied identifiers and the first-party identity cache can support recognition for the same tenant and source. Do not assume automatic cross-source, cross-device, or cross-domain identity linking.
Example: one person visits three times. Hardal can record three sessions. Without a recognized visitor ID, those sessions do not establish how many different people visited. With a matching visitor ID, the Consented Visitors metric can count the recognized identity once over that period.
Engaged sessions
An engaged session contains at least one event in the shared Key Events / Engaged events selection. Several selected events within one session still count as one engaged session.
For example, a session with two selected events contributes two Key Events and one engaged session. A session containing only unselected events contributes no engaged session.
Review the Key Events guide to configure this selection. It does not set Acquisition's conversion events.
Which report should I use?
- Use Events to inspect occurrences and parameters.
- Use Sessions to follow the event timeline of a visit.
- Use Consented Visitors to count non-empty visitor IDs in the report scope, not all people who may have visited.
- Use Acquisition to analyze the conversion credit assigned under its selected model and traffic scope.
See Identify Visitors for implementation and Metrics Glossary for exact report definitions.