is maintained by the LaTeX Project. At the LaTeX Project's website you can find installation versions for Linux, Mac OS, Windows, and Online editors/services.
can be written in any text editor. I personally use Emacs. While Emacs (just like Vim) is a very powerful text editor, it should be noted it has a very steep learning curve. Hence, many recreational users choose an editor with an integrated environment like Kile.
A more versatile text editor which doesn't have a wall of a learning curve with it, is Sublime (you might also like to try Atom). To use Sublime effectively, you will want the plugin which you can obtain from GitHub. There are also various sources talking you through the installation and to get you started, e.g., video, tutorial, tutorial, tutorial, video,video.
At last, there are some resources for .