automate the process of compiling using clang with "make"

 for example:

make hello

....make executes clang with various command-line arguments

execute the resulting executable:

make hello

specify executable file name for clang compiler

 clang -o hello hello.c

-o is a "command-line argument", or a "flag" , or a "switch"

run a program from the command line in Unix

 ./a.out

clang - C compiler

 clang stands for "C language"

for example:

clang hello.c

ls command in Unix

 ls stands for "list"

hello world program in C

 #include <stdio.h>

int main(void)

{

printf("hello, world\n");

}

standard i/o library in C

 stdio.h

#include <stdio.h>

"cd" Unix command

 cd stands for "change directory"

an example would be:

cd ~/dir1

"mkdir" Unix command

 mkdir stands for "make directory"

an example would be: 

mkdir ~/directory1

Commands in Unix are case sensitive

 This means that a capital letter and a lower case letter are treated as different

"~" in Unix command Line

 ~  represents the home directory in Unix command line