An assembler program which is converted into machine code in assembler language. It takes the controls and basic operations of assembly code and converts into a binary code that can be recognized by a specific processor type.
Assemblers are similar in that they compilers to produce executable code. However, the most simplistic assemblers because they convert the low-level code (assembly language) into machine code. Since each assembly language is designed for a specific processor, the assembly of a program is performed using a simple mapping one-to-one assembly code into machine code. Compilers, on the other hand, must convert generic high-level source code into machine code for a specific processor.
Most programs are written in programming languages and high level are compiled directly into machine code using a compiler. However, in some cases, the code assembly can be used to customize the features and to ensure that they perform a specific manner. Therefore, FDI is often editors so they can create programs of the two languages high and low.