Geany is a small and lightweight Integrated Development Environment. It was developed to provide a small and fast IDE, which has only a few dependencies from other packages. Another goal was to be as independent as possible from a special Desktop Environment like KDE or GNOME - Geany only requires the GTK2 runtime libraries.
Some basic features of Geany:
Syntax highlighting
Code folding
Symbol name auto-completion
Construct completion/snippets
Auto-closing of XML and HTML tags
Call tips
Many supported filetypes including C, Java, PHP, HTML, Python, Perl, Pascal