Using RVM Gemsets

One of the most powerful, useful and often overlooked features of RVM is the gemset. A gemset is a separate gem directory, so the gems in one gemset don't conflict with the gems in another gemset. A common usage would be to install Rails 2 in one gemset, and Rails 3 in another. Since they're in different gemsets, there's no possibility of them interfering with each other.

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