Most code editors are similar to notepad.exe in that they are "text editors", but unlike notepad.exe they have functionality built into them to send the code into the compiler.

As I use Notepad++ a lot and take screenshots of code inside it, I sometimes disable the display of line numbers in the editor window. Unfortunately, this means I usually forget how to enable them ...

XML Notepad 2007 is themed around the same kind of just-the-text-ma'am simplicity of Windows' Notepad, but does add relevant features for markup language hacking.