PRODIGY ADVANCE2 consists of three elements.  The POWER PACK transforms the power from your mains socket ready for the Base Unit.  The BASE UNIT is the brains behind the operation.  It contains all the technology you need to send DCC commands to your trains and accessories.  However short of turning the power on and off youll find your closest companion is the Walkaround controller which plugs straight into the Base Unit.   The WALKAROUND is a hand-held controller that you use to send your commands to the Base Unit which then sends them on to the relevant decoder on your layout.  You control the speed and direction of your trains from here.  One of the key features of DCC operation is that each of your locomotives has a numeric address which you select as and when you want to run that locomotive.   DCC allows you to run it anywhere on your railway at the same time as other trains are moving as well.  You can operate points (individually or route set) and signals from the Walkaround.  You can use it to programme your decoders to replicate the running characteristics of your locomotives or even introduce a speed clock that allows you to run a 24 hour timetable within one operating session.   The possibilities are almost endless with DCC and with locomotives becoming available with factory-fitted decoders as standard we are entering an exciting new era.  Of course you can also retro-fit your older locomotives with decoders if you wish.