What does the instruction #include<stdio.h> mean

Hi,

The hash symbol simply says to handle this statement with the C pre-processor. The include simply means to include the standard C library header file when C compiles the program. What happens is that the pre-processor pastes code from the header file into your program so that you can reuse functions that were already written. In this case, it is the standard input/output header file so you'll be able to use functions such as printf, scanf, and so on.

I hope this helps.

-S