Okay, I will try to answer your question without confusing you.
IMAX is a workout. It is the original interval step workout Cathe made years ago. The IMAX 2 and IMAX 3 workouts have followed in its footsteps.
Body Blast is a series of workouts that Cathe put out in 2001 or 2002. It is made up of several different workouts. You can buy the whole series or only buy the workouts that interest you.
Body Max is a killer circuit workout that Cathe made sometime in the 1990's. It is comprised of a step routine, then a plyo/lower body section, then an upper body section, then ends with an ab section.
Boot Camp is another circuit workout that Cathe made in 2000 or 2001. It is part of the "Intensity" workout series. Boot Camp is made up of circuits..one minute of cardio,one minute of lower body,one minute of upper body, and one minute of abs. That sequence is repeated 7 or 8 times.
Hope that helps some, Renee