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Unit 4: VB Programming Fundamentals

is re-created, Visual Basic reallocates memory for all variables and resets them to their default
values (0 for numeric values, “” for strings, Nothing for object variables).
4.3.13 Public vs Local Variables

A variable can have the same name and different scope. For example, we can have a public
variable named R and within a procedure we can declare a local variable R. References to the
name R within the procedure would access the local variable and references to R outside the
procedure would access the public variable.

Success Story of Programming
Overview of Programming Language

The history of programming language gives us the complete details of gradual development
of programming language since its origin. The idea of computer programming language was
based on the concept of difference engine of Charles Babbage. It was in the year 1822 that
this difference engine was used for the first time to transfer task related command to the
computer system. History of programming language shows that programming language has
undergone substantial changes over the last few decades.
Earliest Forms of Programming
Initially the difference engine of Charles Babbage was used as gears to perform the quan-
titative tasks. Physical motion was the primitive version of computer language. Following
the introduction of ENIAC in the year 1942, the electric signals started its journey in the field
of computer programming. The electric signals followed the same mechanism used by
difference engine. However, the difference between the two lies in their modes of operation.
Modern Versions of Programming Language
The history of programming reveals that the modern version of programming language was
launched in 1957 in FORTRAN format. FORTRAN, designed by IBM, served as a medium for
translating formula. However this form of programming language was the simplest of all
the versions used so far.

The Algol language introduced in the following year was a major breakthrough in the
history of programming. Algol has contributed substantially in the development of modern
programming languages like, C, C++ and Pascal. The programming language Pascal, pre-
sents a unique combination of FORTRAN, ALGOL, COBOL and some other commonly used
languages.
Questions
1. Explain the concept of language.
2. Give some Modern versions of Programming language.

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