When Riffyn sees the same resource type on both the input and output of a step, it assumes the resources will be just “passing through.” That is the resource that goes out is the same as the one that comes in. For example, if a fermenter is listed as both an input and output on a step, Riffyn will just pass through the fermenter resource from input to output.
But sometimes that’s not what you want. For example, you might have a cell culture come into a sampling step. Of course, cell culture will come out too. But the culture that comes out is an aliquot or sample of the original, with its own sample ID and independent tracking. You can tell Riffyn this is the situation by marking the resource type as “Sample of” or “New”. This will force Riffyn to generate new resources and resource IDs on the output, instead of passing them through. Both “Sample of” and “New” do the same thing in terms of generating new resources, they just prepend your output resource type with a different word.