Botany. 1  a tuft of silky hairs at the end of a seed. 2  the leafy crown of a tree; cluster of leaves at the end of a stem. 3  a terminal cluster of bracts, as in the pineapple.
The flexible pads are called base-isolators, whereas the structures protected by means of these devices are called base-isolated buildings. The main feature of the base isolation technology is that it introduces flexibility in the structure.
The basic difference is the pin of the transistor that is grounded. The common collector has the collector pin grounded, common emitter has the emitter pin grounded and common base, as you guessed it, has the base pin grounded. The following article explains the differencnes perfectly.