What is Assembly Language in Computer

Assembly language is a computer programming language (a language that is used to make computer programs). It was introduced by David John Wheeler. It is a low-level programming language (closer to a machine). Machines can understand assembly language in a better way than that of a high-level language.

The language which enables instructions to be described by letters rather than numbers is called assembly language. It is also called Symbolic Language. The program that is written in this language is known as an assembly language program or symbolic program. This programming language uses Mnemonics in place of 0's and 1's (binary code) to represent opcode.

This language uses symbolic addressing capabilities which simplifies the programming process because the programmer does not need to remember the exact location of data. The programmer can express an address number to symbolic data by using symbolic addressing.

Example:

                      MOV  5,   AC      10101011
                      MOV  6,   BC      11010011
                      ADD  AC,  BC      10101011

Assembly language uses a translating program for translating assembly language programs into machine language. This translating program which translates the assembly language program into machine language is called an assembler.

The assembler is a system program that is supplied to the computer system. A symbolic program written in assembly language is called a source program.

The source program is then converted into machine language by the assembler and this converted program is then referred to as object program.

Assemblers are designed in such a way that they catch errors automatically. If we use an invalid mnemonic or name that has not been defined before. The assembler will print out an error indication.

Features of Assembly Language in Computer

It is based on Mnemonics rather than numeric operation code or numeric opcode.
Data is declared by making use of decimal notation.
It helps in specifying the symbolic operand.

Advantages of Assembly Language in Computer

1. Easier to Understand and Use: Assembly language is easier to understand and use because mnemonics are used instead of numeric opcodes. Symbolic programming is easier to write than that of machine language programs.

2. Easier to Modify: Assembly language programs are easier to modify than that of machine language programs. This is so because assembly language is easier to understand and hence it becomes easy for a programmer to correct and modify the instructions when required.

3. Easy to Locate and Correct Errors: When there are some errors in the assembly language program, they are easier to find and correct because of the use of mnemonics instead of numeric opcodes.

4. Easily Relocatable: In assembly language programs, we can easily move programs from one section of memory to another section.

Disadvantages of Assembly Language in Computer

1. Assembly language is machine-dependent. That's why programs written for one model of a computer cannot be executed on another one. This means that it is not portable from one machine to another.

2. An assembly language programmer must be an expert who knows all about the logical structure of the computer.

3. It is difficult to write assembly language programs. This also takes too much time to write the programs.

What is Assembly Language in Computer