OSRIC is a free compendium of the rules of 1e, just as Swords & Wizardry is a restatement of the rules of 0e.  We're not affiliated with OSRIC, although Matt Finch, the author of Swords & Wizardry, also created the first draft of OSRIC.  The credit for OSRIC's phenomenal success goes to Stuart Marshall ("Papers & Paychecks"), who turned the original draft into a polished and brilliant product.
Download OSRIC 2.0
Download OSRIC 1.0