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Low-Level Language (LLL)

                A low-level language is a programming language that is machine dependent. A program
                written in machine dependent language runs only on one particular type of computer. There
                are two categories of low-level languages:

                Machine Language

                Machine language is the only language understood by the computer. It is also known as
                the first generation language (1GL). Machine language is very difficult for programmers to
                use because it only consists of two digits, 0 and 1, called binary digits or bits. Where the bit '0'
                represents the OFF state and the bit '1' represents the ON state.


                Assembly Language
                Assembly language is also known as second generation language (2GL). It is the language in
                which program codes are written in the form of alphanumeric symbols called ‘Mnemonics’

                instead of 0 and 1. In the assembly language, a programmer writes abbreviations such as A
                for addition, C for compare, L for load, and M for multiply. Because of this feature, it is also
                known as ‘Symbolic Language‘.


                High-Level Language (HLL)
                High-level language  is  a programming language  that  enables  a  programmer to  write

                programs that are  machine independent. This type  of languages  are considered  as
                high-level languages because they are closer to human languages and away from machine
                languages.
                The main advantages of high-level languages over low-level languages is that they are easier

                to read, write and maintain. Let's discuss about some high-level languages.

                Third Generation Languages (3GL)

                In third generation languages (3GL), the programmer writes a series of English like words
                that tell the computer what to accomplish and how to do. Many third generation languages
                also use arithmetic operators such as * for multiplication and + for addition. Some early
                procedural 3GL are BASIC, PASCAL, C and FORTRAN. Some other advanced object-oriented
                3GL are C++, Java, and C#.


                Fourth Generation Languages (4GL)
                The fourth generation languages also use English like statements. They specify what
                the program should accomplish without explaining how. A 4GL is fast and requires less
                time  and  effort  on  the  part  of  the  programmer.  In  fact,  4GLs are so easy to use and
                programmers with very little programming background can develop programs. Examples

                of 4GL are SQL, Perl, Python, etc.






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