KompoZer is a complete web authoring system that combines web file management and easy-to-use WYSIWYG web page editing.

KompoZer is designed to be extremely easy to use, making it ideal for non-technical computer users who want to create an attractive, professional-looking web site without needing to know HTML or web coding.

Amaya is a Web editor, i.e. a tool used to create and update documents directly on the Web. Browsing features are seamlessly integrated with the editing and remote access features in a uniform environment. This follows the original vision of the Web as a space for collaboration and not just a one-way publishing medium.

Work on Amaya started at W3C in 1996 to showcase Web technologies in a fully-featured Web client. The main motivation for developing Amaya was to provide a framework that can integrate as many W3C technologies as possible. It is used to demonstrate these technologies in action while taking advantage of their combination in a single, consistent environment.

Amaya started as an HTML + CSS style sheets editor. Since that time it was extended to support XML and an increasing number of XML applications such as the XHTML family, MathML, and SVG. It allows all those vocabularies to be edited simultaneously in compound documents.

Amaya includes a collaborative annotation application based on Resource Description Framework (RDF), XLink, and XPointer. Visit the Annotea project home page.

 Xylescope not only helps in understanding and utilizing web standards, it also uses web standards to achieve its magic. Xylescope's source views are taking advantage of Safari's rendering engine to achieve their unique formatting.

While Xylescope transparently converts source code into richly structured HTML, the formatting of the source views is completely governed by style sheets that can be modified by the user! Every single detail of the way source code is presented is completely under your control. This might seem mind-boggling at first but you will soon become familiar with the new power it provides.

Aquamacs is an Aqua-native build of the powerful Emacs text editor. By "Aqua-native," we mean more than just the fact that this version of Emacs runs as a standard OS X application.  Aquamacs features extensive customization: it will feel and behave mostly like an Aqua program - while still being a real GNU Emacs with all the ergonomy and extensibility you've come to expect from this world-class editor. It's beeen adapted by David Reitter, based on GNU Emacs by Richard Stallman and many others. Aquamacs has been downloaded more than 200,000 times since we started keeping track.

TextWrangler is a powerful and richly featured tool for composing, modifying, and transforming text stored in plain-text files.

Text Editing and Manipulating

• Powerful single and multi-file search & replace
• Flexible ‘grep’ style pattern-based search and replace based on PCRE (Perl-Compatible Regular Expression)
• Sort Lines and Process Duplicate Lines plug-ins offer grep pattern support for sorting, extracting, and handling text
• Find Differences to compare two versions of a text file and merge the differences
• Support for a wide variety of BBEdit plug-ins
• Support for rectangular text selections
• Built-in text transformations: Zap Gremlins, Change Case, Entab/Detab, and more
• Open and save files in a variety of character sets, including Unicode (UTF-8 and UTF-16) files
• Supports editing of multi-byte and Unicode text
• Quick Search window
• Perform incremental searches
• Open and save files in Mac, Unix, DOS, and Unicode line-ending formats
• Integrated support for Mac OS X’s spelling service
• Hard or soft wrap text however you prefer
• Quoted text rewrapper
• Multiple Undo
• Multiple Clipboards
• Splittable editing windows
• Auto-Indent

Programming

• Syntax coloring and function navigation for ANSI C, C++, Fortran, Java, Object Pascal, Objective-C, Perl, Python, Rez, Tcl, TeX, and Unix shell scripts
• Automatic language guessing and User selectable per/document language setting for supported languages
• Integration with Mac OS X developer help
• Ability to function as an integrated external editor with Project Builder 2.1

OS Platform Integration

• Comprehensive AppleScript support: scriptable, recordable, and attachable
• Ability to integrate TextWrangler with Unix tools and scripts, by means of the “edit” command-line tool
• Authenticated saves (you can modify files not owned by you, provided that you are an administrative user)
• Support for Quartz text smoothing on Mac OS X 10.1.5 and later.
• Support for Mac OS X Services
• QuickTime translation support
• Automatic backup of files when saving (optional)
• Optional Emacs keybinding support

Other Useful Features

• Extensive FTP/SFTP support open and save text files located on remote FTP servers
• FTP tool supports Mac OS Keychain and use of alternate ports
• FTP Browsers provide persistent view of remote site directories
• Integrated support for FTP access through Interarchy and many other third-party FTP clients
• FTP server discovery using Bonjour
• Support for a wide variety of BBEdit plug-ins & the ability to develop your own plug-ins
• Configurable key assignments – set keys for commands
• Integration with Super Get Info
• Disk browsers – view directory listings and open files
• Floating window list

Smultron is a free text editor for Mac OS X Leopard 10.5 which is both easy to use and powerful. It is designed to neither confuse newcomers nor disappoint advanced users. It should work perfectly for a whole variety of needs - like web programming, script editing, making a to do list and so on.

Smultron has all open documents in a list with beautiful Quick Look icons to your left just like e.g. iTunes so you can easily switch between many documents - you can also choose to display them as tabs if you prefer it that way.