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What is Java?

Java is a programming tool (as C, C++, BASIC, Pascal or Logo) used for creating computer applications. Some of its most outstanding characteristics are:

  • A same application can work in different types of computers and operating systems: Windows, Linux, Solaris, Mac OS X... as in other intelligent devices.
  • The Java programmes can be independent applications (which runs in their own window) or "applets": small interactive programs that are embedded on web pages and can be displayed in any type of browser: Explorer, Mozilla, Opera...
  • It is a "object-oriented" language. This means that the programmes are built from independent modules, and that these modules can easily be transformed or extended.
  • Its development is supported by a wide group of companies and organizations which is bound up  with the spirit of collaboration that inspires the Clic project.

You can find more information on Java in http://java.sun.com.

What is Java WebStart?

Java WebStart is a system that facilitates the downloading, installation, launching and automatic updating of Java applications. Its mechanism of operation is:

  1. The first time that you want to launch an application, you must to go to a web page and click on a textual or graphic link. For example, to start JClic you must click on the corresponding button on this page.
  2. Java WebStart is launched and downloads the components needed by the application. Once downloaded, it usuallly asks the user for permissions and starts off the programme.
  3. From there there are three ways of starting the application:
    1. By returning to the web page and clicking again in the link.
    2. By launching the Java WebStart control panel, looking for the icon of the application and clicking on it. You will find the control panel searching in the Start menu - Programmes (in Windows) or in the Applications folder - Utilities in Mac OS X. In Linux and Solaris you can usually launch it by writing "javaws" in a terminal.
    3. By creating an icon in the desktop and/or in the start menu. The versions of Windows and Mac usually ask the user whether he wants to create these icons the second time that an application is launched. See the FAQ for more information about how to create these icons.
  4. If at the moment of launching the application you have Internet connection, WebStart checks whether there is any new version of the program and, if it exists, it downloads and installs it automatically.

WebStart is a standard feature in the most modern versions of Java (from 1.4).

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