What is command line editing and file name completion?
Command line editing lets you recall previous commands using the arrow keys. Also you can use emacs style commands to edit it. File name completion is when the computer finishes the name of your file after you enter the first few characters. If file name completion is enabled, you can type emacs he followed by the Tab key. It will complete it to hello.c. Of course, it depends on what files are actually in the current directory. You may need to change your shell (see below).
