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Examples of fifth generation languages include Mercury and OPS5.
Natural language is very easy to use. Natural languages are often associated with expert systems
and artificial intelligence. For example, if a program is written in 4GL to get the names of students
whose marks exceed 95, it might be written as:
SELECT LAST-NAME, FIRST-NAME FROM STUDENT WHERE MARKS > 95.
A natural language version of the same program might be written as:
TELL ME THE NAME OF STUDENTS WITH MARKS OVER 95.
Natural languages are often associated with expert system and artificial intelligence. These
systems are popular in the medical and scientific fields, but are not widely used in business
applications.
Advantages of High-Level Languages
A high-level language is user-friendly.
A high-level language is similar to the English language with its vocabulary of words and symbols,
therefore it is easier to run.
A high-level language requires less time to write a program.
A high-level language is easier to maintain.
A high-level language is problem-oriented rather than machine-based.
Programs written in a high-level language can be translated into machine language and therefore
it can run on any computer with an appropriate translator.
A high-level is independent of the machine on which it is used, i.e., programs developed in
high-level languages can be run on any computer, i.e., they are machine-independent.
Disadvantages of High-Level Languages
A high-level language has to be translated into machine language by a translator, which wastes
a lot of the computer's time.
The object code generated by a translator might be inefficient as compared to an equivalent
assembly language program.
i + LANGUAGE TRANSLATOR
A language translator is software that converts a high-level language program into a machine
language. There are mainly three types of language translators:
Assembler
An assembler is a program used to translate assembly language into machine language so that
the computer can understand it.
Compiler
A compiler is a program that converts the entire source program into machine language before
executing it. It converts the entire program into machine language at once. It displays the errors
for the whole program together.
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