Control a rail system in miniature with great realism has always been the dream of all fans of modeling.
In epochs "less technology", the most used technique was to dissect the track into several sections, each controlled by an electrical circuit. 
Lo svantaggio di questo metodo è quello di avere configurazioni circuitali abbastanza complesse e spesso molto difficili da gestire.
Verso la meta degli anni 80, in piena rivoluzione informatica, si cominciarono ad applicare tecniche digitali al controllo dei plastici. 
Today the most common technique is called DCC (Digital Command Control).
In a DCC system the signal power of the track consists of a sequence of digital pulses that contain the control information for locomotives and accessories (exchanges, traffic lights, etc.).
These pulses are generated by a control station controlled by a microcomputer. Inside of locomotives and accessories is a special device (decoder) which receives these pulses, recognizes those proper and implements the commands contained in them. The decoder recognizes the information of its relevance thanks to an address entered in the command sequence.
The functions of the decoder can be modified by the user through a programming mechanism. This allows you to easily update the system without heavy interventions on connections. 
The figure below shows the block diagram of a typical DCC command station.

• A control module that provides the user interface for the generation of digital pulses (Command Station).
  
• A module that amplifies the pulses generated by the digital control module (Booster)
  
• A module that receives signals confirmation by decoder during the programming operations (Ack Detector).