I was wanting to tinker around with TCL/TK programming. I tried to invoke the wish shell, but got this error: $ wish The program 'wish' is currently not installed. You can install it by typing: sudo apt-get install tk So, I tried to apt-get install tk: $ sudo apt-get install tk Reading package lists... Done Building dependency tree Reading state information... Done tk is already the newest version. 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. But it's already installed... Where did wish go?