If you have worked with Sublime Text Editor then you may be familiar with what a Document Map is. There is a section (sidebar) at the right side of the editor with gives an overview of the complete document in pretty tiny font. Document Map is really useful when working with large documents and you have to move quickly to a section of that document. Its much more quicker to move within the file using Document Map instead of scrolling (you may understand the pattern of your code too, say where the function starts and ends looking at the map)
Notepad++ has this feature too (ver 6.6.8). Just click on the icon just next to Function list. When you click on it the Document Map will be loaded at the right side.