These are the plug-in modules designed to provide functionality and connectivity to your Tibbo Project System. Their pins have a classic 2.54mm (0.1-inch) pitch, so they can be installed on standard prototyping boards also.
Tibbits are divided into Tibbit modules (Mx) and Tibbit connectors (Cx). There are also hybrid (Hx) Tibbits that combine the two. The number following the letter indicates the width of the Tibbit, and a trailing S or T indicates Short or Tall (e.g. M2T is twice as wide and is taller than M1S). Tibbit connectors have convenient hooks that additionally secure them to the board's edge.
The Tibbit M blocks are color coded based on their function (see image to the right). The C and H blocks are always orange (and always Tall).