Newbie question on raw adjustments in LR

Question

I am just trying to get a handle on how lightroom works. If I make adjustments in the Develop module are the adjustments made to the RAW file itself or are the adjustments written as instructions within LR. When I use ACR in bridge I notice that I can then open lightroom and SEE the ACR adjustments. Is the same thing happening in LR
I am asking this because I started using Aperture but did not like the fact that I could only see my adjustments from within Aperture. Is lightroom better at handling this??
Thanks,
Kevin

Answer 1

>>You don't NEED to output to jpeg or tiff...
Don't follow you. You don't output the file? You just view it?
>>You could edit, have those edits written as metadata to file... and print all in LR... then go back to same exact file and reset it to its exact original state.
The edits are applied to the original data while the data is sent to the printer.
>>plus these edits are all virtual... you can edit the crap out of a jpeg (without exporting)
Yes, and that's very useful and a reason why metadata edits are so cool. Of course, one could say you could do the same thing using adjustment layers on a JPEG. There's just a much larger overhead for each and every layer.
>>the old Save As method required multiple copies of the same image eating up hard drive space, and cluttering folders.
Yup although again, with layer sets, you could build a dozen different renderings and turn them on and off in any combo to see any set of corrections. Laborious compared to metadata editing. None of this of course is non destructive to the final data.
Now things get interesting with DNG if and when one can build multiple rendering instructions inside this format. Far more useful for raw but hopefully where we'll go in the foreseeable future. Embed multiple rendering sets ala Layer Sets inside the DNG but without the massive overhead.