I just recently got into dance improvisation.  It's a whole new world for me.  I understand you know a thing or two about it? 
Improvisation is a free way to express yourself through dance. Artists like Michael Jackson are the epitome of dance improvisers and they love creating new forms of dance/expression. 
It makes sense MJ was a dance improviser.  He was so unique!  How can you tell the difference between normal dance performers and improv dancers?
Improv dancers always try to be unique each time they dance, so you won't see a lot of repetition. But normal performers follow rituals and strict choreography that they practice over and over. 
Fascinating!  Do Improv dancers have any techniques to guide their performance since they don't rely on strict choreography?
free movement that improvisation is centered upon the mover is able to explore authentic feelings and inspirations.
The history of improvisation in dance.
The history of improvisation in dance Western Theatrical Dance.
In the Renaissance Italy, improvisation was used and valued in performance and participatory dances. In performance-based settings in the 15th century, dancers used improvisation to alter or replace various steps or motions, particularly hand gestures, in choreography for the purpose of creating variety. This use of improvisation declined in the 16th century as set,
not only about creating "new" movement but is also defined as freeing the body from habitual movement patterns (see Postmodern dance and Judson Dance Theater). Dancer and singer Michael Jackson combined improvisation in both of those definitions, insisting that he had interest in performing a dance to "Billie Jean" only if he could do it a new way each time.
A lot of improvisation is focused on finding a deeper way of comprehending otherwise concealed thoughts or feelings of an individual. Through the emphasis of instinctual, unpredictable,