Geany is an open-source, cross-platform text editor and IDE (Integrated Development Environment). It is designed to provide an easy-to-use interface for development requirements such as editing source code, compiling and debugging code, running external programs, and managing project files. It is one of the most popular code editors in the Linux community, and is available on Windows and macOS as well. Geany supports many programming languages and has a number of features such as syntax highlighting, code completion, auto-indentation, code folding, and symbol name auto-completion. It also has an integrated debugger for debugging your code. Additionally, it supports external plugins for customizing the editor and adding features such as version control and file browsing. Geany is a fast, lightweight, and feature-rich code editor that can be used by both beginners and experienced developers.
nano is a text editor, not an IDE
Discontinued The program is no longer updated. The latest version, 4.2.25, released on October 28, 2012, can still be downloaded from the official website.
Discontinued Aptana is still under development on GitHub but the latest version, 3.6.1, was released in October 2014. It lacks Java 8/9 features, as well as more recent JavaScript and HTML 5 features.
Notepad++
Atom
Visual Studio Code
Sublime Text
Vim
Eclipse
Brackets
gedit
GNU nano
PyCharm
GNU Emacs
Kate
Komodo Edit
Qt Creator
Notepad2
Adobe Dreamweaver
Aptana Studio
Neovim
Bluefish Editor
UltraEdit
Atom is not an IDE, just a text editor.