C++ Basic Syntax

                                                                        The basic syntax of C++

When we consider a C++ program, it can be defined as a collection of objects that communicate by invoking each other's methods. Let us now briefly look into what a class, object, methods, and instant variables mean.

• Object − Objects have states and behaviors. Example: A dog has states - color, name, breed as well as behaviors - wagging, barking, eating. An object is an instance of a class.
• Class − A class can be defined as a template/blueprint that describes the behaviors/states that object of its type support.
• Methods − A method is basically a behavior. A class can contain many methods. It is in methods where the logics are written, data is manipulated and all the actions are executed.
• Instance Variables − Each object has its unique set of instance variables. An object's state is created by the values assigned to these instance variables.        

                                           C++ Basic Structure

Let us look at a simple code that would print the words Hello World.

Let us look at the various parts of the above program −

• The C++ language defines several headers, which contain information that is either necessary or useful to your program. For this program, the header <iostream> is needed.
• The line using namespace std; tells the compiler to use the std namespace. Namespaces are a relatively recent addition to C++.
• The next line '// main() is where program execution begins.' is a single-line comment available in C++. Single-line comments begin with // and stop at the end of the line.
• The line int main() is the main function where program execution begins.
• The next line cout << "Hello World"; causes the message "Hello World" to be displayed on the screen.
• The next line return 0; terminates main( )function and causes it to return the value 0 to the calling process.