You might have heard people talk about programs, applications, or apps. But what do these words mean? Simply put, an app is software that helps you do specific tasks. Apps for computers are called desktop applications. Apps for mobile devices are called mobile apps.

When you open an app, it runs on your operating system until you close it. Often, you can use more than one app at the same time. This is called multi-tasking.

The word "app" is commonly used for simple applications. Many apps are free or inexpensive. They are available for mobile devices and even some smart TVs.