There are several kinds of Java programs. The most well known program
type is called an applet. An applet is a Java program that can be
executed inside a Java enabled web browser. Applets are often used
to produce animations and built interactive web pages.
However Java is not just for writing cute web animations. Java allows
powerful application to be written that run directly on the Java
platform. These applications include client application and server applications.
In fact almost anything can be written in Java that can be written in any
other language.
The Java API provides a wide range of functionality and components that
support all types of programs. The core API is included in every full implementation
of the Java platform. This core API gives you the following features:
-
The basics - Objects, strings, threads, numbers, input and output,
data structures, system properties, date and time, etc.
-
Applet - The set of conventions used to write Java applets.
-
Networking - URLs, TCP and UDP sockets, IP addresses.
-
Internationalization - Functionality used to develop applications
that can adapt to specific locales and be displayed in appropriate languages.
-
Security - Both low and high level security. Including electronic
signatures, public and private keys and access control.
-
Software Components - These components called JavaBeans can plug
into existing component architectures. This allows third party vendors
to build components that integrate seamlessly into Java environments. JavaBeans
are similar to Microsoft's Active X components or OpenDoc components.
-
Object Serialization - Allows persistence of objects and communication
with remote objects using Remote Method Invocation (RMI).
-
Java Database Connectivity - Provides a platform independent framework
for accessing relational databases.
As well as the core API, Java has several standard extensions. These extensions
provide support for 3D graphics, servers, telephony, collaboration and
multimedia.
Sources:
