You can receive, if you wish, an email alert on a daily basis to get all the new job ads matching to your search criteria. You can also decide to deactivate the alert if you're not currently looking for a job.
To manage the job alert, click on "Edit my criteria" in your dashboard.
The second section is specially dedicated to the alerts.
If you haven't interacted with the job alert for three months, it will automatically be turned off. You then have to untick it in your profile and tick it again to be able to receive these emails.