Occasionally after you log into Drupal administration, you might see a Drupal alert message that looks something like ...

Just click the "Status Report" link and it will take you to the "Status Report" page.

More than likely, you might see a red X as shown ...

saying that your "Cron maintenance tasks" has not been run recently. That would not be surprising, if you had not configured cron jobs with your webhost during the inital Drupal installation. As configuring cron jobs is not something everyone has done before nor is it easy, many do not have cron jobs configured. That is fine. It just means that you have to manually run the cron job yourself every couple of weeks or so.

Notice in the above picture that the "Drupal Core Update Status" is yellow indicating that "No information is available". If cron jobs are not run, Drupal will not be able to tell if update is needed or not.

So it is time to run the cron job manually. To run the cron jobs, just click the link "run cron manually" under the "Cron Maintenance Task" as seen in the above.

After runing the cron job, we see that the "Drupal core update status" has detected that a new security update version of Drupal is available...

So the initial Drupal alert message was informing us that we need to run our cron job. Running the cron job informed us that we need to update Drupal. Once we have updated Drupal to the latest version, we would have cleared our alerts.

See tutorial on how to update Drupal.