It is common for web applications to run background tasks. The applications could need to clear unnecessary files or cache, import third-party data, or even periodically send out email newsletters. Thankfully, all Unix-based have a scheduling utility that makes it possible to automate certain tasks.

A newsletter application plays an important role when launching a new product. As a business, you'd want to collect user interest in your new product or service prior to the launch for the purposes of decision-making.

Sending emails is a vital part of most web applications. There are many instances that may require the sending of emails in your application. For example, when a new user registers for an account, you may want to notify them of this action through the email they have registered with. Certain cronjobs may require the automatic sending of emails to an application's users at regular intervals. When it comes to user authentication, an application can also incorporate the ability to request a password reset.