i got the above video somewhere in badminton central and i really like the contents.

I just have some questions to clarify and i hope the high level players/coaches can clarify this for me.

From the file XiongGuoBaoCD1b.mpg. The trainer is showing footwork trraining.

One method is starting at 00:12:00 and another one starts at 00:13:00. I want to know what is the difference between these two methods and when do you use each(in what situation)? Also, pls advise what is the name or how do these footwork are called?

Thank you.