Visual Basic

Visual Basic (VB) is the third-generation event-driven programming language and integrated development environment (IDE) from Microsoft for its COM programming model. Visual Basic is relatively easy to learn and use. Visual Basic was derived from BASIC and enables the rapid application development (RAD)of graphical user interface (GUI) applications, access to databases using Data Access Objects, Remote Data Objects, or ActiveX Data Objects, and creation of ActiveX controls and objects. Scripting languages such as VBA and VBScript are syntactically similar to Visual Basic, but perform differently. A programmer can put together an application using the components provided with Visual Basic itself. Programs written in Visual Basic can also use the Windows API, but doing so requires external function declarations.

The final release was version 6 in 1998. Microsoft's extended support ended in March 2008 and the designated successor was Visual Basic .NET (now known simply as Visual Basic).

Characteristics

Visual Basic has the following traits which differ from C-derived languages:

Multiple assignment available in C language is not possible. A = B = C does not imply that the values of A, B and C are equal. The boolean result of "Is B = C?" is stored in A. The result stored in A would therefore be either false or true.

Boolean constant True has numeric value −1. This is because the Boolean data type is stored as a 16-bit signed integer. In this construct −1 evaluates to 16 binary 1s (the Boolean value True), and 0 as 16 0s (the Boolean value False). This is apparent when performing a Not operation on a 16 bit signed integer value 0 which will return the integer value −1, in other words True = Not False. This inherent functionality becomes especially useful when performing logical operations on the individual bits of an integer such as And,Or, Xor and Not. This definition of True is also consistent with BASIC since the early 1970s Microsoft BASIC implementation and is also related to the characteristics of CPU instructions at the time.

Logical and bitwise operators are unified. This is unlike some C-derived languages (such as Perl), which have separate logical and bitwise operators. This again is a traditional feature of BASIC.

Variable array base. Arrays are declared by specifying the upper and lower bounds in a way similar to Pascal and Fortran. It is also possible to use the Option Base statement to set the default lower bound. Use of the Option Base statement can lead to confusion when reading Visual Basic code and is best avoided by always explicitly specifying the lower bound of the array. This lower bound is not limited to 0 or 1, because it can also be set by declaration. In this way, both the lower and upper bounds are programmable. In more subscript-limited languages, the lower bound of the array is not variable. This uncommon trait does exist in Visual Basic .NET but not in VBScript.

OPTION BASE was introduced by ANSI, with the standard for ANSI Minimal BASIC in the late 1970s.

Relatively strong integration with the Windows operating system and the Component Object Model. The native types for strings and arrays are the dedicated COM types, BSTR and SAFEARRAY.

Banker's rounding as the default behavior when converting real numbers to integers with the Round function. ? Round(2.5, 0) gives 2, ? Round(3.5, 0) gives 4.

Integers are automatically promoted to reals in expressions involving the normal division operator (/) so that division of one integer by another produces the intuitively correct result. There is a specific integer divide operator (\) which does truncate.

By default, if a variable has not been declared or if no type declaration character is specified, the variable is of type Variant. However this can be changed with Deftype statements such as DefInt, DefBool, DefVar, DefObj, DefStr. There are 12 Deftypestatements in total offered by Visual Basic 6.0. The default type may be overridden for a specific declaration by using a special suffix character on the variable name (# for Double, ! for Single, & for Long, % for Integer, $ for String, and @ for Currency) or using the key phrase As (type). VB can also be set in a mode that only explicitly declared variables can be used with the command Option Explicit.

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JAVA

Java is an object-oriented programming language developed by Sun Microsystems in 1990s. Since then, Java has gained enormous popularity as a computer language. Java was chosen as the programming language for network computers. It is a universal front end for enterprise database. Sun Microsystems states that, “Java is a simple, object-oriented, distributed, secure, architecture, robust, multi threaded and dynamic language. The program can be written once, and run anywhere”. One of the most significant advantages of Java is that, it has the ability to move easily from one computer to another. It also has the ability to run the same program on many different operating systems. With such exemplary benefits, Java is a hot favorite among techies and software professionals.

Java has significant advantages compared to other languages. Java language is easy to use and therefore easy to write, compile, debug. Moreover, it is easier to learn when compared to other programming languages. Since Java is object-oriented, it allows you to create modular programs and reusable codes. Platform-independent, Java is a robust language. The language lays more importance on early checking for errors, since Java compilers can detect many problems during the time of execution of an application. Java is multithreaded, since it has the capability for a program to perform several tasks simultaneously within the same program. Java Development has gained a significant position in the industry with programmers and developers finding it easier and more effective than many other languages.

Java applications are designed to be compiled and then interpreted at runtime, unlike the