Last year I watched a local production of Cats. Thanks to my kids, I’ve seen the Cats DVD countless times: and our local production was a bang-on facimilie of the DVD - which I presume closely matches the original stage production.
How is the integrety of performances maintained from company to company? The music’s easy - musical notation has been around for centuries. Likewise set design (drafting) and costumes (clothing designs). (I was surprised to learn our local company didn’t order pre-made costumes, rather they made everything from scratch!)
But the dancing: After our company pulled out the musical score, the set designs, and costume drawings, what did they pull out to begin dance rehersals? Is there a standard choreographic notation?
Collectively, it’s called choreography (literally translates as dance writing) or dance notation.
Two of the more common methods used to write it down are Labanotation and Benesh Movement Notation.
A brief description of Benesh can be found here and a run-down of Labadanotaion’s available here.
Or…they could have watched the DVD. 
Then what did the DVD producers watch, smart guy?
Thanks to gotpasswords and friedo (and Cecil) for the one-two (three, sir) knockout of my ignorance.
I wonder what notation Michael Jackson used for those group dance routines in his videos.
Probably nothing, since he had video. The way I see it, choreography notation is only necessary when you want to preserve the choreography from one set of performers for another set without having a go-between who actually danced it and can teach it, and without having a recording of the dance itself.
Even once you’ve got the notation, you still need someone who can interpret it and dance it to teach to the rest of the dancers. Which is probably just as hard to get as someone who’s either performed it before, or seen it and memorized it, and can dance it to teach to the rest of the dancers.
Are these notations still used now that video is so prevalent?