PROGRAMMING AND COMPILER

INTRODUCTION

Any inputs which are put into computer must be changed into machine language so as computer to understand and compile the data and give out the output.

COMPILER Is a program that converts from source code (programming language) to machine language.Machine language is representation of a computer program which is actually read and interpreted by the computer. A program that translates from a low level language to a higher level one is a decompiler.

Short history
Software for early computers was primary written in assembly language. Higher level programming language were not inverted until the benefit of being able to reuse software on different kind of CPUs started to become significantly greater than the cost of writing a compiler.The very limited memory capacity of early computers also created many technical problems when implementing a compiler. At the end of the 1950's, machine-independent programming languages were first proposed. Several experiment on compilers were developed.The first compiler was written by Grace Hopper, in 1952 for the A – O programming language.

There are some terms which are use in different areas like;
Hardware Capable of carrying out a wide variety of decisions and tasks.To do so needs to be given a set of instructions in a form which it can understand
Software Is a collection of set of programs to accomplish a certain goal
Programming Language Is artificial language used to write a sequence of instructions that can be run in the computer.
Translator a language translator is a type of system software that translates a program written in a second, third or higher generation language into machine language
Interpreters Translates source code instructions into machine language and executes it one statement at a time
Syntax grammar rules
Semantics meaning of command
Computer programming languages are divided into three types
Machine languages directly understand by the computer, Assembly languages and Higher-level languages

Generations of computer Language
The different stages of computer programming languages over time (should not be confuse with hardware generation),The lowest level of computer programming language use computer natural language (0,1) Simply to slow, tedious and error-prone and what was wrong with machine code.

Assembly language it was in the second generation. Is the low level programming language Uses abbreviation or easily remembered words instead of numbers and it uses translator or converter.

High level language it was the third generation. These resembles human language such as English,most third generation language can be used in more than one kind of machine,.the language is interactive that is User and computer communicate with each other directly during the writing and running program ,Examples of High Programming Language are BASIC,PASCAL,C/C++,COBOL,FOTRAN PYTHON and JAVA

The forth generation was the Very high level Language that allow users to develop programs with fewer commands compared with the 3GL.Allow users to specify the desired results without having to specify detailed procedures needed for achieving the results.Consists of report generators, query languages, application generators and interactive DBMS.4GLs may not entirely replace 3GL because they are usually focused on specific tasks and hence offer fewer options. Improve productivity because programs are easy to write.
The next evolutionary step being developed. Design to give people a more human (natural) connection with computers.The language are human language like English, French etc.

Selection of programming language the selection of language highly depends upon the nature of activity and availability of the simplest language to solve the desired task or problems. Obviously, there is no best language for all situations. The best language might depend on many things: Type of program, Reason the program is built, Size of program, Programmer familiarity, Ease of program verification, Proof of correctness, desk checking, test and Simplicity of semantic and syntax.

Importance of computer programming language
Important for students in all disciplines of computer science, improve your ability to develop effective algorithms, increase your vocabulary of useful programming constructs
To make it easier to learn a new language, make it easier to design a new language and Soft ware development, Interface writing.

Generally, the programming languages are challenging on learning due to new languages are being invented the skilled programmer are needed and it is difficult in debugging,