You do not need help,you need to learn.
First thing,you need to learn better emglish,otherwise will be very difficult for you to understand the answers.
Second,you are not going to learn by asking in this way.
You need to read about DVB and TRANSPORT STREAM.
I advise you to google for documents related.
in any case,this are your answers
EMU = refers to a device that emulate certain decryption by using the same algorithm
DZ-Viaccess 2.6 ECM Decrypter V4.00 = assuming the name tell you what it is,it decrypts the ECM of certain viaccess encrypted provider.
ECM = in DVB,it refers to a PID that carry encrypted packets that contain the control words that are going to be used to decrypt the video.