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Hello World
High Level Languages
To get a good understanding of how programs will generally be started and general C formatting we can write some test code. We will create a program which prints out the text "Hello World" by opening a .c file in our IDE and typing the following:
Let's look at a Hello World example written in C piece by piece.
Using this test code we can take away some notable points.
#include <stdio.h>
The #include statement is used to include a library into the program. This allows us to use functionality of the library and call to it. stdio.h is the standard in and out library for C and will be defined at the beginning of the program. Other libraries can be included using #include <libraryName>
/* Comments */
Wrapping text in /* */ will create multi-line comments which are not read by the compiler. These are useful for leaving behind notes for yourself as well as other developers. Since they are multi-line comments they can be as long and as many lines as you want.
Simply putting // in front of text will create a single-line comment. This comment will end on the next line without the need for an ending terminator.
int main()
Functions can be made and called upon to complete pre-programmed tasks. The main function is always called upon as the first function. Other functions will be called from the main function. This function holds a block of code wrapped in curly braces {}. This code is what is inside of our function and which will execute.
printf("Hello World");
The printf statement is called upon to send text to our standard output. printf will output the contents of the parentheses which define the text. This command is terminated with a semicolon, without doing so would cause an error while compiling. Without including the stdio.h library this code would not execute properly.
return 0;
The return statement will end the program. The following 0 is a status tag for the program. If a program exits with the status 0 it ran successfully, if a program ends in another status (usually -1 for error) something threw the program off from its designated path. Some compilers and IDEs will generally add the return statement automatically.
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