Cathode Ray Tube

A vacuum glass tube into which a electron beam is ejected from a cathode. The electron beam creates a lightning effect when it hits a substrate on the inner front of the flatted tube.


Dots Per Inch

Resolution measurement for printers.



A monochrome vector graphic symbol. Usually constructed from splines or Bézier-curves.

Glyphs are the character definitions inside a font.


Pixel Per Inch

Resolution measurements for Displays.


Scalable Vector Graphics

2D Vector Graphics Drawing System based on a XML-Schemata.

SVG is rather a visualization system than a vector graphics drawing system. It features: filters, animations, hierarchies, transformations and viewports.


Tool Command Language

Pronounced »tickel«.

Tcl is a simplistic, yet powerful language, which features list and strings as data types.

Thin Film Transistor

An electronic manufacturing process. Combined with Liquid Crystal Displays. A transistor is being embedded in the display and boosts the signal needed to realign the liquid crystal.


Widely used Graphical User Interface Toolkit. Originally fashioned after the Motif Toolkit under X Window System.

Tk can be used with: Lisp, Ruby, Python, Perl, C, Tcl, Erlang, Limbo, Ada, Cobol...

Tk is the Graphical User Interface of the Inferno Operating System.



A predominantly rectangular shape inside a Graphical User Interface. In general actions or event handlers are associated with it.

»button«, is an example for a window. The class is »Button« and each instance of a button may have a »-command« attribute.


See Window.

White space

The area without any active control. Usually referred to as background. The behavior of a dialog can be deduced by how its active elements are surrounded by white space.

It is however critical not to include excessive amount of white space inside active controls. In this situation the recognition of the control as such is severely negative affected –an important reason for separating geometry management and window.