I saw no difference between an applet and an application from the definition of the former:
In computing, an applet is any small application that performs one specific task, sometimes running within the context of a larger program, perhaps as a plug-in.
So is there really some difference when not using applet specifically just as Java Applet?
An applet is a Java based approach to embedding a Java application in a web page.
An applet is a program written in the Java programming language that can be included in an HTML page, much in the same way an image is included in a page. When you use a Java technology-enabled browser to view a page that contains an applet, the applet's code is transferred to your system and executed by the browser's Java Virtual Machine (JVM). For information and examples on how to include an applet in an HTML page, refer to this description of the tag.
An application on the other hand is more generic in scope and can include a desktop application such as Microsoft Word or a cloud based application such as Gmail.
Applets by in large are never mentioned unless relating to the Java implementation and concept. In addition applets are no longer as popular as they once were due to other emerging web based technologies.
Using the term applet to refer to a small specific application that performs one specific task may be accurate according to Wikipedia but would unfortunately fail in the effective communication department.
Applet are "small applications". They differ from "real applications" in the fact that they normally are embedded in a narrow environment in which and only in which they can function, implementing a very limited functionality.
The term applet is more often used for browsers, where the <applet> tag is used in HTML to call Java embedded applications. Bandwidth constraints forced such applications to be rather small, while security considerations forced them to use only software already installed on the computer, which for Java is its runtime (JRE).
However, this term is also used (or misused?) with an expanded scope, and may then pertain to JavaScript, ActiveX, Flash or even HTML chunks (using the <DIV> tag), but is not limited to these environments. It then refers to to a small and severely limited application with a small display (or none at all) which requires very little local installation (none is preferred).
Exactly the same tools are used to compile applets as are used to compile applications, so the only real difference in the end is the applet's small physical size, limited functionality and no need for local installation.
An applet is an application that either
runs within a bigger application, and/or
runs under a runtime environment that limits what it can do
Applications normally have access to the full API provided by the operating system,.
An "applet" per se would only have access to an API provided by a runtime or other application. Typically such APIs aren't as full featured or flexible as a full OS API.
