On a standard Drupal installation, you need to run Cron Jobs (or tasks as they are called sometimes). Drupal will actually give you an status error if you don't run a cron job after you install Drupal.

Cron is driven by a configuration file that specifies Unix to run certain commands on periodically on a given schedule. This is how Drupal knows when to publish an article at a certain time and how it indexes the site for it's built in search engine. Without running Cron, Drupal would never do these items.

Most hosting companies will allow you to run cron tasks for Drupal, but what happens if you can't? There is a third party module out there, called Poormanscron, that will run the cron tasks that Drupal requires without setting up a Cron Job in the Unix Configuration file. Sound difficult? It isn't!

Once installed (I have a show on how to install third party modules), Poormanscron, will run the cron tasks every 60 minutes (you can change this if you'd like). Instead of relying on Unix's schedule, Poormanscron relies on visitors to trigger the tasks. Once a visitor goes to you your, the module checks to see of a cron job has been run in the last 60 minutes, if not, it runs it. It's that easy.

I have not had any issues with Poormanscron. This module is great for those times when you can't get those cron jobs running properly.