Programming may be defined as “The process of creating steps for a computer to perform a desired task.” Thus programming is a means of controlling a computer’s Central Processing Unit and its components (computer memory/ storage, the arithmetical unit and the logic unit) as well as the various peripherals attached to the computer, to perform certain tasks based upon the commands we give it. These commands may be in a form very similar to readable English (in which case they are called High Level Languages) or in a cryptic code including a multitude of zeros and ones (in which case they are called Low Level Languages). In between these two extremes is a hybrid sometimes called Mid Level Programming Language; this includes features of both high and low level languages. Each developer of a computer program works with a code, which to be intelligible to other programmers, is developed into a syntax or language. Syntax therefore can be described as a group of reserved words that are used to give commands and accomplish tasks using a particular computer language. If the language developer wishes that the world use his/ her particular language, he will get it tested, copyrighted and published. The language is then available for testing and use by other programmers.

Programmers have been writing computer code and languages for the last 50 years or so. BASIC was the world’s first common intelligible language for the microcomputer or home computer (Personal Computer).
Structured Programming is a technique for organizing and coding computer programs in which a hierarchy of modules is used, each having a single entry and a single exit point, and in which control is passed downward through the structure without unconditional branches to higher levels of the structure. In this new approach to programming called the Modular Approach, the whole structure of the program is drawn out first, the entire project is divided into logical but separate parts, and the parts are then linked together.
Let us now delve into the structure and characteristics of the following four programming languages: C++, Java, Visual Basic and Assembly Language.

C++:

The original C language was developed by Dennis Ritchie and Brian Kerrighan in 1974. Quick C and C++ are improvements on the original C language. C++ was designed and implemented by a Scandinavian called Bjarne Stroustrup. C++ is a general purpose programming language that leans towards systems programming. It is better than the original C because it (a) supports data abstraction (b) supports object-oriented programming and (c) supports generic programming. The structure of a C Program is similar to Fortran. C uses functions much in the same way as Fortran’s functions and subroutines; a main function ( ) combines all the functions.

Being an object oriented language, C++ has the following advantages: (1) Debugging is easier (2) It is possible to reuse the code (3) There is more flexibility possible in applications.

C++ supports the properties of encapsulation and data hiding through the creation of user-defined types, called classes. Users of a well-defined class do not need to know how the class works; they just need to know how to use it.
C++ supports the idea of reuse through inheritance. A new type, which is an extension of an existing type, can be declared. This new subclass is said to derive from the existing type and is sometimes called a derived type.
C++ supports the idea that different objects do "the right thing" through what is called function polymorphism and class polymorphism. Polymorphism refers to the same name taking many forms.

C++ has been accredited by the American National Standards Institute (ANSI), and similar institutions in the UK and Germany. The ANSI standard is an attempt to ensure that C++ is portable--that code you write for one compiler will compile without errors, using a compiler from any other vendor.
Source: Characteristics of a C++ Program (www.olemiss.edu/orgs/ieee/Nithya/tsld024.htm)

Java:

The name Java is a trademark of Sun Microsystems and refers to the programming language developed by Sun and released in 1995. Java is used to create executable content that can be distributed through networks.
Java brings interactivity to the Web through applications that can all give the user immediate feedback and accept user input continuously through mouse or keyboard entries.
Java animates pages on the Web and makes interactive and specialized applications possible. This gives Web information providers the opportunity to create a hypertext page that engages users in continuous, real-time, and complex interaction. Java profoundly changes the Web because it brings a richness of interactivity and information delivery not possible using previous Web software systems. Java makes it possible for programmers to create software that can be distributed across networks and run on many different kinds of computers.
Java developers can create virtual worlds that are not only three-dimensional but also animated and interactive. Animation isn’t limited to cartoon figures. Animation can also be made interactive, where the user has some input on its appearance. Another variation involves providing the user with a way to interact with an interface to get feedback. This is real-time interactivity.

The handlers and applications that Java makes possible have the potential to dramatically extend what can be browsed on the Web. The protocol and content handlers, like the executable content Java makes possible as applets, can be distributed as needed to requesting Java-enabled browsers.
Java enriches the interactivity of the Web and transforms the Web into a software delivery system: Java’s essential design as a language to deliver executable content makes it possible for programmers to create software of any kind and deliver it to users of Java-enabled browsers. Java technology is not necessarily limited only to the Web. Java technology can be deployed in embedded systems, such as handheld devices, telephones, and VCRs. Electronics firms have been working to use Java technology in these devices.

Visual Basic:

BASIC is an acronym for Beginner's All-purpose Symbolic Instruction Code, developed by a group of Stanford professors as an improvement over Fortran. Over the years, there have been improvements to the original BASIC, such as QBasic. Microsoft introduced a new programming language, Visual Basic, a few years ago. The advantages of Visual Basic are:
• Visual Basic is based on the QBasic programming language, so programming newcomers find Visual Basic friendlier than other languages.
• Visual Basic is designed from the ground up to be a Windows programming language. Inherent in Visual Basic's fundamental design is the event-driven program concept. Visual Basic is Event-Driven and Procedural.
• Visual Basic is graphical in its programming approach. You can literally create a complete and working Visual Basic program by moving picture icons on and off the screen without ever writing one command in Visual Basic's programming language.
• A program written in Visual Basic looks almost exactly like the output screen that results.
Source: Visual Basic In 12 Easy Lessons by Greg Perry (Sams Publishing Co.)

Assembly Language:

Assembly language refers to the earliest of languages developed for the computer. It was an improvement over the complicated mechanisms or circuitry devised for manipulating the computer’s switches in On and Off states. The syntax of Assembly Language comprises of commands such as MOV for move, PUH for push etc. Different versions of assembly language have been developed for different computers such as the Z80, the Commodore and Microsoft PC. Modern day assembly language uses the hexadecimal system, comprising of digits from 0 to 9 and alpha characters A to F. An assembler is used for compilation and library functions.

People do not like Assembly Language because it is too difficult to use. However it is a fact that even the most powerful computer does not understand anything else than machine language. The job of all programming languages is to take the source code that you type in a programming language and to convert it to machine language so that the computer can execute those instructions.