Using this page to "crowd-source" some text for http://www.tcl.tk/software/tcltk/8.6.html . **Object Oriented Programming** The commands of the '''[TclOO]''' package are now part of Tcl itself. This gives Tcl a built-in object system that is fully dynamic, class-based, and includes advanced features such as meta-classes, filters, and mixins. New version 4 of the popular package Itcl (aka '''incr Tcl''') is also included, granting support for some traditional OO Tcl programming out of the box as well. **Stackless Evaluation** **Enhanced Exceptions** New commands '''try''' and '''throw''' and a wealth of new '''-errorcode''' values enable far more precise trapping and handling of exceptions with a familiar construct. **Batteries Included** Tcl delivers in the '''pkgs''' subdirectory a bundled collection of third-party packages built and installed along with Tcl. **Thread-enabled Operations** A thread-enabled default build, a bundled '''Thread''' package, and new command '''interp cancel''' make Tcl 8.6 ready for your multi-threaded programming tasks. **SQL Database Powered** The bundled Tcl DataBase Connectivity ('''tdbc''') interface package makes it possible to write your SQL database-powered scripts decoupled from any particular database engine. The bundled '''sqlite3''' and '''tdbc::sqlite3''' packages supply a powerful and popular SQL database engine ready to use. **IPv6 Networking** The '''socket''' command now recognizes numeric IPv6 addresses as valid values for its ''$host'' argument where platform support exists. **Built-in Zlib Compression** New command '''zlib''' provides utilities to handle compression of data and streams. **List Processing** New commands '''lmap''' and '''dict map''' enable the elegant expression of transformations over Tcl containers. **Stacked Channels by Script** New commands '''chan push''' and '''chan pop''' expose the power of stacked channels without the need to write C code. **Other New Features**