Parent page: Programming Applications
Emacs is the extensible, customizable, self-documenting real-time display editor. It is very powerful, yet idiosyncratic; to use it we advise following its own tutorial, and after the tutorial one should use its effective help system, learning gradually. One can access the tutorial via the menu (Help -> Emacs Tutorial) or via the keyboard shortcut C-h t (that is: type Control-C, then release Control and type 't').
Emacs 24.3 (released on March 11, 2013) is readily available in Ubuntu repositories for Ubuntu 14.04 (Trusty) and Ubuntu 14.10 (Utopic). Simply install the emacs package. Emacs 24.4 was released on October 20, 2014 with a few additional features, and isn't readily available for either Ubuntu 14.04 nor Ubuntu 14.10. To install the latest Emacs 24.4, I downloaded and compiled the source archive. It was quick and easy, but if you want a trivial installation then simply install the ready-made Ubuntu package for Emacs 24.3.
Emacs Lisp packages Directory
The directory ~/.emacs.d/ is the location for additional per-user Emacs-specific files written in Emacs Lisp programming language. Since it is located in the home directory (~/), it is unique for each user, just like the ~/.emacs init file.
Starting with Emacs 22, if the startup configuration file ~/.emacs does not exist, Emacs will try ~/.emacs.d/init.el and ~/.emacs.d/init.elc. The user independent startup file for all Emacs flavors (Emacs 19, Emacs 20, xemacs) will load /etc/emacs/site-start.el.
The Emacs Wiki is a community website which collects ELisp code, questions and answers related to ELisp code and style; introductions to ELisp packages and links to their sources; complete manuals or documentation fragments; comments on features, differences, and history of different Emacs versions, flavors, and ports; jokes; pointers to clones and Emacs look-alikes, as well as references to other Emacs related information on the Web.
If one is curious about the text-based user interface
If you launch Emacs via the graphical launcher then it will choose its default GUI mode. To see what its TUI (text-based user interface) looks like, one can execute emacs -nw in a console, terminal or terminal emulator. If there isn't a graphical window system - for example if one executes Emacs remotely over SSH - then the emacs command will choose the TUI by default. Note that instead of executing Emacs on the remote computer over SSH, you can also execute Emacs locally and use the local Emacs to access the remote files. This way you can work in GUI mode and with the additional advantage of not requiring Emacs to be installed in the remote end.