At this point, you can write some code in Emacs and save it to a file. But what do you do with that code? First, you need to compile it. This means you need to run a program called the Compiler which translates the code you wrote into actual machine instructions. The compiler will then produce a file which you can execute by typing its name at the command prompt much like any other program. However, before you can compile the code you need to add some pound include directives. You'll learn more about these and the compilation process later in this lesson. Once you have added any necessary pound include directives, you can run the compiler like any other command. The compiler you are going to use is called GCC and it takes some command line options to specify things like what to call the program it creates and how much it should warn you about code that seems questionable. You will learn more about these things in an upcoming lesson. You will also learn about a tool called Make which will simplify building large programs with many files andor a lot of options passed to the compiler. Once the code is compiled, you can run the resulting program. In this example, we instructed GCC to produce a program called Hello. We can run it with./hello. The dot and slash specify that the hello program should be found in the current directory, which we'll also talk more about later. You can see that the program ran and printed this output, Hello, world! Now that you have seen the basic overview of compiling and running code, let's dive into the details.