(adsbygoogle = window.adsbygoogle || []).push({}); The stuff that tells the computer what to do is called the software
What runs the stuff is called hardware

A computer’s CPU (processor) cannot speak or interpret C++. The only thing a CPU can speak is machine code. Machine code is very very very hard to understand, but two things must be noted. First, each machine code instruction is composed of a number of binary digits, each of which can only be a 0 or a 1. These binary numbers are often called bits (short for binary digit).
For example, here is a x86 machine language instruction: 10110000 01100001

Second, each set of binary digits is translated by the CPU into an instruction that tells it to do a very specific job, such as compare these two numbers.
In the olden days, people had to write programs in machine code language (which was very hard and time consuming). So thats why there is programming languages like C++ (c++ is one of the best, loads of programs are written in c++, e.g. firefox). The assembly language (C++) is not readable by the CPU. Instead, it must be translated into machine language by using an assembler. High level programming languages are: C, C++, Pascal, Ada, Java, Javascript, and Perl, are all high level languages. Programs written in high level languages must be translated into a form that the CPU can understand before they can be executed (machine code). There are two primary ways this is done: compiling and interpreting.

A compiler is a program that reads code and produces a stand-alone executable that the CPU can understand directly. Once your code has been turned into an executable, you do not need the compiler to run the program. Although it may intuitively seem like high-level languages would be significantly less efficient than assembly languages, modern compilers do an excellent job of converting high-level languages into fast executables. Sometimes, they even do a better job than human coders can do in assembly language!

Here is a simplified representation of the compiling process:

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An interpreter is a program that reads code and essentially compiles and executes (interprets) your program as it is run. One advantage of interpreters is that they are much easier to write than compilers, because they can be written in a high-level language themselves. However, they tend to be less efficient when running programs because the compiling needs to be done every time the program is run. Furthermore, the interpreter is needed every time the program is run.

Here is a simplified representation of the interpretation process:

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Any language can be compiled or interpreted, however, traditionally languages like C, C++, and Pascal are compiled, whereas “scripting” languages like Perl and Javascript are interpreted. Some languages, like Java, use a mix of the two.

High level languages have several desirable properties. First, high level languages are much easier to read and write.

Here is the same instruction as above in C/C++: a = 97;

Second, they require less instructions to perform the same task as lower level languages. In C++ you can do something like a = b * 2 + 5; in one line. In assembly language, this would take 5 or 6 different instructions.

Third, you don’t have to concern yourself with details such as loading variables into CPU registers. The compiler or interpreter takes care of all those details for you.

And fourth, they are portable to different architectures, with one major exception, which we will discuss in a moment.

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The exception to portability is that many platforms, such as Microsoft Windows, contain platform-specific functions that you can use in your code. These can make it much easier to write a program for a specific platform, but at the expense of portability. In these tutorials, we will explicitly point out whenever we show you anything that is platform specific.


If you are still dazzled
Please don't read on
Take a few minutes to read this lesson again
And make notes if needs be
It only gets harder


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Perhaps remove the images from the original source?

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