Monthly Archives: October 2015

High-Level Languages

High-level languages are a major advancement in programming languages. High-level languages are much easier to use than assembly or machine languages, because they are designed to use a more English-like syntax. Some examples of high-level language statements are: (a) total = 1 + 3, and (b) name = “Ken”.

High-level languages promote platform independency, i.e., they can be executed on many different machine types. High-level languages might require the use of a compiler. A compiler is used to convert the high-level language code, into machine language code, that can be understood, and executed by the computer. Some high-level languages might require an interpreter, instead of a compiler. An interpreter “interprets” the high-level programming code, line-by-line, as the code is executed. Interpreted languages are not compiled ahead of time.

Interpreted languages greatly increase platform-independency because the programming code is converted to machine language code on the machine in which the program is executing, instead of being converted to machine language code on the programmer’s computer.

High-level programming languages can either be procedure-oriented or object-oriented.

Procedure-oriented Languages

Procedure-oriented languages concentrate on the major tasks that the program needs to perform. Some examples are: (a) calculating sales tax, (b) totaling and order, and (c) inputting customer data. Procedure-oriented languages must be instructed line-by-line, from the start of the task, until task completion. The programmer decides the order in which the computer processes instructions, i.e., the correct sequence. Some examples of procedure-oriented languages are: (a) COBOL, (b) BASIC, and (c) C.

Object-oriented Languages

Object-oriented languages focus on objects that the program can use to accomplish its goal. These might be real-world objects, for example: (a) an employee timecard, (b) a customer, or (c) an employee paycheck. These objects can be used in more than one program, thereby promoting code reuse, which saves time and money. Some examples of object-oriented programming languages are: (a) C#, (b) Java, and (c) C++. These languages can also be used to create procedure-oriented programs.

Assembly Language

Assembly language is slightly more advanced than machine language, and it simplifies a programmer’s job by implementing the use of mnemonics, instead of 0s and 1s. Mnemonics are memory aids which serve as alphabetic abbreviations for computer instructions. There are a few mnemonics which are common amongst various assembly languages. ADD, and MUL, are a couple examples of common mnemonics. Example assembly statements (ASM) would be: (a) MUL bx, ax; and (b) ADD bx, ax.

A program needs to be written in machine language before a computer can understand it; therefore, all assembly language code must be converted into machine language code before the program can be understood and executed by the machine.

An assembler is a program that is designed to convert assembly language programs into machine language programs. This conversion process turns the mnemonic-based assembly language code into the binary code that is required for execution; therefore, assembly language provides an easier way to write machine language code, as the programmer does not need to work directly with the binary-based machine language.

Assembly language is easier to use than machine language; however, it still requires highly skilled and trained programmers to be used effectively. Like machine language, assembly language is platform dependent. This means that programs generally have to be (at the very least) slightly modified, before they will run on another type of machine.