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# Identity and sessions – Product Analytics pocket guide

Canonical URL: https://posthog.com/learn/product-analytics/pocket-guide/identity-sessions

Chapter 02

# Identity and sessions – Product Analytics pocket guide

Twig records each filter selection as a `stay_filter_selected` event. Its `destination_type` property shows which destination was chosen. This tells the team what happened, but not *who* was behind the interaction.

PostHog adds two identifiers that help connect the event to the visitor and visit that produced it:

-   `distinct_id` groups events under the same [identity](https://posthog.com/docs/product-analytics/identify.md).
-   `$session_id` groups events from the same [session](https://posthog.com/docs/data/sessions.md).

## Group events into one visit

Put yourself in the shoes of an anonymous Twig visitor. Select **Forest**, then **Coast**, and notice how the `distinct_id` and `$session_id` remain the same:

Reset

Twig

Filter by destination typeForestCoast

![Dark A-frame cabin among autumn trees, with a gravel path leading to the entrance at dusk](https://posthog.com/static/cabin-52b343c8c87096a619df7bf1a904bcea.jpg)

### Adiron-shack

Adirondacks, New York

4 guests · 2 bedrooms · 2 baths

**$355** / night USD