Events are customer activities on the website (visits to a website, adding a product to a shopping cart) and also user's activities towards customers (such as sending messages to them). They are the basic input used for analyses and further actions in Synerise. 


## Use of events
---

Events are used mainly in the **Decision Hub**. Because events and their parameters are measurable, users can build various types of analyses. They can group customers into segments, create funnels, count the occurrence of events, their sum, average, minimum and maximum values, prepare reports, calculate conversion rates, build loyalty point structures and so on.

They are used in the **Automation Hub** as well. A workflow created in this hub can by triggered by a particular behavior of a customer and their behavior can also determine progressing through the workflow as well.

The **AI hub** analyzes events such as visits to the website and purchases to predict churn rate or predict the most successful conversion path. Whereas the statistics of the **AI Hub** are prepared based on product purchase, product search and search click events.

## Event types
---

There are two types of events:
- default events - these events are collected as a result of implementing a tracking code into the website, SDK event tracking, automations, and more. Examples: `page.visit`, `message.send`, `transaction.charge`. A full list is available [here](/docs/assets/events/default-events)
- custom events - these are all events defined by a user and added on the interface or sent to Synerise. 

## Collecting events
---
Events are collected as a result of:
- [Implementing a tracking code](/docs/settings/tool/tracking_codes) into a website
- [SDK event tracking](/developers/web/event-tracking)
- API tracking

To power the application with archival data, users can also import historical events to Synerise. 

## Event definitions
---

In **Data Modeling Hub > Events** - You can check the event definitions with description (if added) and parameters assigned to the events. The definitions manage what kind of data is accepted by an event or added to that event when its [enriched](/docs/assets/events/adding-event-parameters#enriching-events-with-data-from-catalogs).

<figure>
<img src="/api/docs/image/54176ad07f146575310749eba44b7c2f42c1b327/docs/assets/events/_gfx/event-list.png" alt="Event details available on the list of events" class="full" >
<figcaption> Event details available on the list of events </figcaption>
</figure>

## Viewing events
---
In **Behavioral Data Hub > Profiles > Customer's profile > Activity list**, The activity list contains actual events received from customers. Clicking an event results in displaying the details:

  <figure>
  <img src="/api/docs/image/54176ad07f146575310749eba44b7c2f42c1b327/docs/assets/events/_gfx/event-details-activity-list.png" alt="Event details available on the activity list on the customer's profile" class="full" >
  <figcaption>Event details available on the activity list on the customer's profile</figcaption>
  </figure>


## Event retention
---
Each event in Synerise has a defined time range when it is available in the random-access memory. It means that it's available for Synerise users in the application for creating analyses or available on the activity list on the customer's profile.

Custom events added by a user are available for 30 days by default. 

Other events, generated by Synerise in response to the customer's behavior on the website or by actions taken towards customers by Synerise users have various retention period. By default, the retention of events (if not stated differently under a contract):
- page visits - 30 days
- message events - 90 days
- transactions - lifetime

## Denylist of event parameters
---

The following event parameters are denylisted by default in every workspace. This means you cannot access them in filters or use them as filter conditions across the Synerise platform. Additionally, denylisted event parameters cannot be used for [event enrichment](/docs/assets/events/adding-event-parameters#enriching-events-with-data-from-catalogs).  


<div class="admonition admonition-note"><div class="admonition-icon"><svg xmlns="http://www.w3.org/2000/svg" fill="none" viewBox="0 0 24 24" stroke="currentColor" stroke-width="2.5"><path stroke-linecap="round" stroke-linejoin="round" d="M13 16h-1v-4h-1m1-4h.01M21 12a9 9 0 11-18 0 9 9 0 0118 0z" /></svg></div><div class="admonition-body"><div class="admonition-content">

The denylisted event parameters may occur in the event details (in the **Raw data** tab) on the [profile activity list](/docs/crm/crm-profile#activity-list).

</div></div></div>


| Event name              | Denylisted event parameters                                                                                 |
|-------------------------|-------------------------------------------------------------------------------------------------------------|
| [All events](/docs/assets/events/event-reference/common-parameters#base-parameters)            | snr-original-time, nonTradingDays, ssuid, uuid, eventUUID, time, clientId, client_id,<br> businessProfileId, business_profile_id, formFieldsMapping, formData, ogTags, apikey, tck |
| [`session.end`](/docs/assets/events/event-reference/web-and-app#sessionend)             | session_start_event_uuid, last_activity_date                                                                 |
| [`transaction.charge`](/docs/assets/events/event-reference/items#transactioncharge)      | products`*`                                                                                                    |
| [`page.visit`](/docs/assets/events/event-reference/web-and-app#pagevisit)              | init, last, color, current, ecookies, res, ver, u24_visits, snr_sdk_version                                  |
| [`dynamicContent.show`](/docs/assets/events/event-reference/dynamic-content#dynamiccontentshow)     | ip                                                                                                          |
| [`recommendation.generated`](/docs/assets/events/event-reference/recommendations#recommendationgenerated)| results, xRequestId                                                                                          |
| [`recommendation.view`](/docs/assets/events/event-reference/recommendations#recommendationview)     | xRequestId                                                                                                  |
| [`recommendation.click`](/docs/assets/events/event-reference/recommendations#recommendationclick)    | xRequestId                                                                                                  |

`*`The list of products in the transaction is preserved; a separate [`product.buy` event](/docs/assets/events/event-reference/items#productbuy) is generated for each product.