Tcl Httpd 2.3.7 is the last stable "2.3" release. Tcl Httpd 3.0* adds threading and SSL support. There are two sorts of distributions. tclhttpd3.4.tar.gz will just contain Tcl Httpd tclhttpd3.4-dist.tar.gz is a bundle that includes Tcl and other packages. For more info, see http://www.tcl.tk/software/tclhttpd/