Java Introduction

Program:

Program is a Collection of Statements or set of instructions used to perform a specific operation.

Software:

Collection of programs is known as “Software or Computer Based Application”, which can be used to operate computer or various devices. Computer based application or software’s can be developed to using a special language is called Programming Language.
Example:
C
C++
Java
.Net
Python etc……

Classification of computer based application:

Computer based application are classified into two groups (types)
1. Desktop Applications.
2. Network Based Applications.

Desktop Application:

This is an application which can be executed in a single computer by the single user at a time.
Example: OS Software
Music players
Some gaming software’s etc….

In general desktop applications developed using “C or C++ “languages.
The main disadvantage with desktop application is no sharability that means it is not possible to share the desktop application from one computer to another computer. To overcome above disadvantage network based applications are introduced.

Network Based Application:

If any application supports network concept is known as Network based application.
If any application is shared or used a multiple computers by the multiple user at a time is known as Network based applications.
Example:
sateeshm.com , Facebook,Gmail, Online Banking, .. etc

Network:

Inter connection of computers known as a network .The main advantage with the network is sharing of data application. Network is classified into following types based on distance.
1.LAN
2.MAN
3.WAN
4.Internet
5.Intranet
6.Extranet

Local area network (LAN):
Inter connection of computers with in a building is known as Local area network.
Metropolitic area network (MAN):
Inter connection of computers with in a city is known as Metro politic area network.
Wide area network (WAN):
Inter connection of computers wide range of area(Group of MAN'S).
Internet:
Inter connection of computers which on existing on globe is known internetwork or internet.
Intara network:
Inter connection of computers within an organization is known as Intra network.
Extra Network:
Inter connection of computers between different organization is known as Extra network.

In General any Network application can be developed using java or.Net.

Example: Hospital based application.
Banking applications
All websites like yahoo Google, FaceBook, etc….

History of Java:

In the year 1983 an independent software developer called bjarne stroustroup was developed C++ language but it is not supporting network concept and platform independent features. To overcome these problems a new programming language was developed Mr. James Gosling in the year 1991 called OAK at SUN Micro system.
OAK not meeting the industrial language so that it was revised and rereleased in the year 1995 with a new name called JAVA. Java was developed by James Gosling and his team in the 1995 at sun micro system.
first time java was introduced as a programming language with version java 1.0.
From java 2.0 onwards it is available in three categories
1.J2SE
2.J2EE
3.J2ME

J2SE (Java 2 Standard Edition)(Core Java):

It is used to develop
1.Console Applications
2.Windows Applications
3.Basic Network Based Applications

1.Console Applications: If any application runs on the Command Prompt.
These are similar to C ,C++ Application.
2.Windows Applications:If any application runs on the Windows Operationg System.

Example:
Calc
MS-Office
OS
Notepad

3.Basic Network Based Applications:If any application runs on the Router.
Example: Router Configurations

J2EE (Java 2 Enterprise Edition):

That means Advanced Java.
which can be used to develop enterprise or internet based applications, later it was renamed as JAVA EE.
Example:Facebook, Gmail ...

J2ME (Java 2 Micro Edition):

which can be used to develop mobile applications. Later it was renamed as JAVA ME.

Note: The latest version of java is 20 and sun Microsystems was takeover by oracle.

Conclusion:

Java is a universal programming language can be used to develop all types of applications
(Console ,Windows , Basic Network Based,Network Based), but as per as software industry consent it was mainly introduced Network based applications.