An applet is a small program designed to perform a specific task. It cannot be executed directly from the Operating System and is designed to be executed from within a larger program or another application. Applets are ideal for small internet applications accessible from browsers due to their small sizes and cross-platform compatibility.
Applets are not fully featured application programs and they perform only a small set of tasks. Examples for applets in Microsoft Windows are Windows Notepad and Microsoft Paint.
Web- based applets can provide new and interactive features to web applications by capturing mouse inputs, providing buttons and check-boxes. Applets can provide features which cannot be provided by HTML alone. Applets can be used for virtual demonstrations and online game creation. Examples of web based applets are: flash movies, 3D modeling and browser games.
In statistics, applets can be used to demonstrate various concepts like mean, median, binomial distribution, sampling distribution, confidence intervals etc.