this is my first time coding
what do you mean by a preprocessor command
Course: https://www.educative.io/courses/learn-cpp-from-scratch
Lesson: https://www.educative.io/courses/learn-cpp-from-scratch/xV9NG6M3YQn
Hi @Aishwarya_Pundir !!
In C++, a preprocessor command is a directive that instructs the preprocessor to perform specific actions before the compilation of the source code begins. The preprocessor is a separate software component that processes the source code before it is passed to the actual compiler.
The preprocessor commands are identified by a hash sign (#) at the beginning of the line. They are executed by the preprocessor, which evaluates and performs the requested actions. The most common preprocessor commands in C++ include #include, #define, and #ifdef.
In the line :
#include <iostream>
The #include directive is used to include the contents of the specified file in the source code. In this case, <iostream> is the file being included, which is a standard C++ library header file. This file contains declarations and definitions for input/output operations, such as reading from and writing to the console.
By including <iostream>, you gain access to the functionality provided by that library, allowing you to use input/output operations like std::cout (for output) and std::cin (for input) in your program. The preprocessor effectively copies and pastes the contents of <iostream> into your source code before compilation, so you can use the declarations and definitions from that file in your program.
I hope it helps. Happy Learning 
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