gcc 8.3.0 compiling

[James Dalton <jamesdalton831@xxxxxxxxxxx>]

    I am new at using gcc. I have ubuntu 18.10 and gcc 8.30. I try 
compiling a simple c program with the following command gcc hyworld.c -o 
hyworld. It seems to compile but when I try to run it I get the error 
message

file type shared library. What am I doing wrong?

program

#include <stdio.h>

main()

{

    printf("hyworld");

    return o ;

}