Question: when I open up the terminal and write the command 

```
cd Desktop  

```

also I have tried 

```
cd /Desktop

```

a message appears that no file or directory was found what I suppose to do? I have logged in as a root but still have the same problem any help?

Answer: 
To enter your user's Desktop directory, run `cd ~/Desktop` (the `~` is expanded into your user's home directory). If your Desktop directory doesn't exist, you can create it via `mkdir ~/Desktop`.
Run this command in terminal,it will help you.

```
cd ~/Desktop
gcc yourfilename.c

```