Some Background on Java
Most authors claim that Java was first developed in order to create a
development environment and programming language that would work across
different computer platforms and the Internet. Due to these efforts
Java has become one of the main development languages for internet based
applications. It can be used for everything from developing
animations and graphics to interacting with users.
Since most of the development within Java is predicated on the need for a language that will work across platforms the language is at times cumbersome and more difficult to work with than a language such as Visual Basic where the developer knows the users have a Windows operating system. On the other hand, the increased range of implementation is often considered worth the extra effort.
But Java can also be used for developing stand-alone applications that will work on a large variety of platforms. While these sorts of applications tend to be more the province of C++, Java has its own development market.
On the internet there are needs to have both client and server side processing and Java is probably the development environment most capable of providing the greatest number of options.
Applets are most likely to be run on the client. Applications are more likely to be distributed and run on a client, though they could be run on a server. Servlets run on a server. JSP pages run on the server. This should show you that Java has a pretty complete set of options for developing for clients and/or servers.
Java is an object oriented language and developers need to be able to create their own classes and objects. While there are quite a few predeveloped classes, the developer needs to have considerable proficiency in object oriented programming to make use of these.
Now we will start developing our own programs.