Have you ever faced a situation, where you clicked on a link given within an application, and the link opens a sort of mini browser, directly within the app, rather than opening up your main web browser?
The reason this happens is Android WebView.
The technical definition of the Android system WebView is that it is a system component for the Android operating system, that allows Android apps to display content from the web, directly inside an application.
Earlier, the Android System WebView was coupled to the operating system, which meant that the utility was only upgraded with every version upgrade for Android. This meant that users had to wait for a year before the WebView feature saw an upgrade and optimizations. However, the WebView utility was separated from the OS when Android 5 was released, and this allowed Google to push updates and bug fixes more regularly through the Play Store.