Jitterbug & Jive
Essentially, Jive & Jitterbug have shared roots as LindyHop, being more like a regional (British Jive) variation. They use many if not all the same moves - albeit with an emphasis on simpler 6 beat footwork which can suit faster tempo music better. Jitterbug is generally a fast moving and visually impressive dance style and is usually associated with 1940's re-enactment societies.
This is what wikipedia says about Jitterbug
Invented in the 1980's by James Cronin of CEROC fame and franchised across the UK, Modern Jive although popular in the UK remains practically unheard of elsewhere. Its popularity has led to many independant organisations teaching the style that has become more commonly known (through some revisionistic re-writing of recent history) as Modern Jive.
As a basic dance style, Modern Jive readily integrates movements from other unrelated dance styles. Modern Jive (in its various franchised forms) seems gernerally to be gravitating increasingly towards Latin Ballroom styles and Salsa (which is a similarly 'army' dance style) sharing many upper body movements but with the addition of more structured footwork.
Modern Jive, typified by organisations such as CEROC and LeRoc is not a Swing Dance style (though it can be danced to mid tempo Swing & Jazz music) since it uses a two-step (step in, step back ...) walking style.
Little emphasis is placed on learning footwork patterns which is its strength (since it is therefore easy to learn) but also its weakness (since the style is ultimately limited to mid-tempo music).
This is what wikipedia says about Modern Jive
This is what wikipedia says about CEROC
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