Notepad++ is a free source code editor and Notepad alternative that supports several languages. (You don’t have to replace Notepad. They can coexist.)
It is very useful for catching an illusive syntax error.
It is easily switchable between languages/styles.
Customization allows you to create User-defined highlighting
and Style Configuration allows you to make it your own.
read more about Notepad++ at http://notepad-plus.sourceforge.net/