Here's the different groups that I think are involved:

- The original inhabitants - the ones who built the "foot" statue.
- The Black Rock people - who I believe washed ashore
- The original Dharma group - Richard's people who I think eventually found out secrets about the island that made them suspect Dharma's true purpose and they eventually rebelled (the Hostiles).
- The second Dharma group - the group that Ben and his father joined. This group was made up of people who understood Dharma's purpose, and some who didn't (like Ben's father) and were simply there to follow orders.
- The third group - made up of Ben and Richard's people. They began recruiting people from off the island (like Juliette).
- A team of scientists - Danielle's people of which only she and her daughter Alex survived.
- I think there is some kind of relationship (but I don't know who knows about who) between Dharma, the Widmore Group (but not Penny), Oceanic Airlines, and the latest group (Freighter People).

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