Computer program


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What is programming?

Computer program is a set of instructions that guide a computer to execute a particular task. It is like a recipe for a cook in making a particular dish. The recipe contains a list of ingredients called the data or variables, and a list of steps that guide the computer what to do with the data. So programming is the technique of making a computer to perform something you want to do.
Programming or coding is a language that is used by operating systems to perform the task. We know computer understands binary languages with digits 1s and 0s. These binary languages are difficult to understand by human; so we generally use an intermediate language instead of binary language. Again the program uses high-level language that is interpreted into bytes that the computer understands. So a programmer writes a source code and uses a tool or interpreter that allows the computer to read, translate and execute the programs to perform a function.
Today there are different user friendly and easily understandable languages supporting different styles of programming. Some of the computer languages are like formula translation (FORTRAN), C, C++, PASCAL, BASIC, Java, C sharp(C#) and many other high-level languages. Further an interpretable p-code or byte code is generated in case some advanced languages like Java and .NET.
These languages enable one to create and perform various kinds of applications. However, in the whole process of programming it is important to understand that a program written in any of the high-level languages needs to be converted to machine language to run on a computer. This conversion is done with a complier or an interpreter. In all kinds of programming languages a complier and if required an interpreter is available. But the basic difference between these two is that the complier converts the entire program into machine code. An interpreter, on the other hand, converts one statement at a time to machine language and executes it.


What is Java, it’s history?

Java is a high-level object-oriented programming language developed by the Sun Microsystems. Though it is associated with the World Wide Web but it is older than the origin of Web. It was only developed keeping in mind the consumer electronics and communication equipments. It came into existence as a part of web application, web services and a platform independent programming language in the 1990s.
Earlier, C++ was widely used to write object oriented programming languages, however, it was not a platform independent and needed to be recompiled for each different CPUs. A team of Sun Microsystems including Patrick Naughton, Mike Sheridan in the guidance of James Goslings decided to develop an advanced programming language for the betterment of consumer electronic devices. They wanted to make it new software based on the power of networks that can run on different application areas, such as computers and electronic devices. In the year 1991 they make platform independent software and named it Oak. But later due to some patent conflicts, it was renamed as Java and in 1995 the Java 1.0 was officially released to the world.
Java is influenced by C, C++, Smalltalk and borrowed some advanced features from some other languages. The company promoted this software product with a slogan named “Write Once Run Anywhere” that means it can develop and run on any device equipped with Java Virtual Machine (JVM). This language is applicable in all kinds of operating systems including Linux, Windows, Solaris, and HP-UX etc.

Where is Java being Used?

The programming language Java was developed by Sun Microsystems in the year 1995. Earlier, it was only used to design and program small computing devices but later adopted as one of the platform independent programming language. The most important feature of Java is its byte code that can be interpreted on any platform including windows, Linux etc. One can also download it freely from the official website of Sun.

As we have mentioned above that java-programming language was only developed for the small devices but now it can be found in a variety of devices like cell phones, e-commerce application, PCs and almost all network or computing devices.

Java is available in different form:

JSP ? Like PHP and ASP, Java Server Pages based on a code with normal HTML tags, which helps in creating dynamic web pages.

Java Applets ? This is another type of Java program that used within a web page to add many new features to a web browser. These are small program used in the programming of instant messaging, chat service, solving some complex calculation and for many other purposes.

J2EE ? The software Java 2 Enterprise Edition are used by various companies to transfer data based on XML structured documents between one another.

JavaBeans ? This is something like Visual Basic and a reusable software component that can be easily assemble to create some new and advanced application.

As far as syntax is concerned, Java is similar as the C programming language but a distinct style of coding. It follows all the general programming features like loops, data types, conditions, curly braces, semi-colon etc. Its a fully featured Object Oriented Programming (OOP) language as it supports all OOP features including classes, modules, inheritance, Polymorphism etc.