Information about Computer Programming

A program is a set of instructions given to a computer for it to perform certain tasks. These instructions are fed into the computer by a programmer. A programmer is the person who sits down and designs the instructions to be fed into the computer in order for it to perform a certain task. So these instructions designed are called software. As a programmer you need to know that there are specific applications that run on individual computers but consider that the vast majority of software applications are used by multiple people to access centrally held data. If you are designing or developing such an application you need to structure it differently to an application that is only going to be used by one user on a single computer such as a calculator for example

Different Languages

All languages are not the same. In order to understand the differences between the hundreds of different computer languages and particularly the limitations of a particular language it is necessary to understand that three types of language.

1. Machine Languages
2. Assembly Languages
3. High-level Languages

Machine Language

Machine language is a language that a machine (computer) can understand and ultimately contains sequences of only 0s and 1s.i.e this language can not be understood by a layman but the computer interprets the language into a language that can be understood by human beings.

Assembly Language

Assembly languages were first developed in 1950’s, and they were reoffered to as Second generation language by then. Assembly languages evolved from programmers creating functions that executed a number of machine code commands in order to save time. This resulted in a language that was much easier to read but could not be understood by computers directly. Assemblers were used to convert the assembly code into machine code.

High-level Languages

High-level languages are simply the next logical step. The level of abstraction is taken even further and complex tasks can be accomplished with a single function. This obviously makes it possible to write software much quicker. Compilers are used to convert high-level code into machine code but this process takes time so interpreters are often used during development to execute code all be it more slowly. C++, Java and Microsoft Visual Basic .Net are examples of high level languages (Java uses a combination of an interpreter and a compiler).

OO Concepts

Early programming languages such as Basic, Cobol and Fortran were only capable of executing commands in a predefined sequence, these were known as Procedural Languages.

 

As applications grew in complexity and power, Event Driven languages such as Visual Basic were introduced. These languages were capable of executing sub-sets of commands when an event, such as mouse clicks, occurred.

 

And then came Object Orientated languages including C++ and Java. Object Orientated languages use blocks of code to define real life objects. The theory is that this gives a logical structure to the code, allowing more flexibility. Applications developed with using an Object Orientated language should also be easier to maintain and grow.