Possible Duplicate:
Support for various features in gedit
I'm currently creating a website for myself in HTML 5, and I've noticed that in the tutorials I'm watching, Notepad++ has little + or - boxes next to the line number which allow for elements of the website to be collapsible. For example, if I pressed the - box next to the section, it would collapse the entire section, and if I pressed +, it would reappear. Is something like this possible in GEdit, since things are starting to get crowded and it would be extremely helpful if that was possible.
If not, can someone direct me to a text editor that does have it (i.e. an alternative to Notepad++ which has about the same features) and works in Ubuntu?
Try Geany.
sudo apt-get install geany
In Gedit, no. Gedit uses a different text control which does not support that feature (small as it may be) so you will need to find another editor if you want code folding.
Try Bluefish, Monodevelop (yes, it uses Mono and I like it!), or Geany. Or you can use one of the many Scintilla based editors available (such as SciTE).