Events can be aggregated over time to produce metrics for your experiments. Create one or more metrics for your experiments to measure the impact.
## Create an event
To create an event that tracks user actions:
Navigate to the _Events_ dashboard and click _New Event_.
Define an event key, a unique identifier that you will reference in your code when you call `
Event keys can contain spaces (unlike experiment keys) to conform to industry event-naming standards. Also, event keys must be unique for the project.
In _Event Tracking Code_, Optimizely automatically populates example code for a Track call with your event key and a `
Click _Save Event_.