> ## Documentation Index
> Fetch the complete documentation index at: https://docs.visitorquery.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Javascript

> Learn how to install the client side code on your website

To install the script you need a project so make sure you have created one.
If you haven't, you can create one [here](https://visitorquery.com/dashboard/projects).

Once you have your project, click on the `Settings icon -> Setup instructions` and add the domain name where you wish to install the script.

Copy the `Public API key` form that window and paste it in the script below by replacing `<project-public-api-key>` with it.

```html theme={null}
<script src="https://cdn.visitorquery.com/visitorquery.js"></script>
<script type="text/javascript">
	window.addEventListener('load', () => {
		window.VisitorQuery.run({
			ApiKey   : "<project-public-api-key>",
			SessionId: "session-id-of-the-user"
		});
	});
</script>
```

Keep in mind that, for security reasons, a Public API key will only work when the request originates from the domain that you have added in the project settings.

## The session id

We recommend using a unique session id for each user session. This can be a random string or a unique identifier that you generate.
The session should not be long lived, this is not something like a cookie that you store for a long time.
It should change if the user closes the tab/window.
Failing to do so could lead to a lot of fals positives when checking the session data due to pollution from other sessions of the same user.

## Install complete

Once you have installed the script, you can create a pageview on your website and the results should start showing in the project's page in the dashboard.
To programatically check a user's session data, use our [REST APIs](/api/guide).