We can automate a number of different types of applications using Selenium. These include web-based applications, mobile apps, and even desktop apps.
Web-based applications are the most common type of application that people automate using Selenium. This is because Selenium was originally designed as a tool for automating web browsers. However,Selenium can also be used to automate other types of web-based applications, such as those built using frameworks like AngularJS or ReactJS.
Mobile apps can also be automated using Selenium. This is often done by using a tool called Appium, which is designed specifically for automating mobile apps. Appium uses the Selenium WebDriver protocol to communicate with mobile devices, so it's possible to use many of the same techniques for automation that we would use for web-based applications.
Finally, desktop apps can also be automated using Selenium. This is typically done by using a tool called Winium, which again uses the Selenium WebDriver protocol to communicate with desktop windows and controls. Just like with mobile apps, many of the same techniques that we would use to automate web-based applications can be used to automate desktop apps as well.