The fork is the product
People typing "what is rpm" mean four different things: a revenue line in an ad dashboard, a needle on a tachometer, a Medicare-billable model of healthcare, or a Linux package format. Every existing page picks one meaning and answers it thinly, usually without a date or an author. This site was built the other way round. It resolves the fork on the first screen, then gives each meaning a wing deep enough to stand on its own. The disambiguation is the product; the wings are the proof it is not a gimmick.
The site is written and maintained by Oliver Wakefield-Smith, founder of Digital Signet, a UK publisher that runs a portfolio of reference and calculator sites about advertising metrics, costs and pricing. Serving four audiences from one domain only works if each wing is held to the discipline its own field expects, so each one runs on a different class of primary document.
What each wing runs on
| Wing | Primary documents | The author's seat |
|---|---|---|
| Revenue | Network help pages, published thresholds and revenue shares | Years of operating ad-monetized sites and reading the same dashboards this wing explains |
| Machines | ISO, BIPM and NIST unit definitions; manufacturer spec sheets | Reference tables maintained directly against standards-body and manufacturer documents |
| Healthcare | CMS and HHS publications, never vendor marketing | Figures quoted from the fee schedule and coverage documents, with the lookup linked |
| Packages | The RPM project's own documentation and current distro docs | Written by someone who has shipped software to RPM-based distributions |
The full list of every document behind every number, with retrieval dates and refresh cadence per data class, lives in the source register. When published content changes, the change gets a dated entry in the public corrections log. If you find a number that has drifted from its source, email oliver@digitalsignet.com with the page URL and the source you checked; verified corrections ship in the next review pass and are logged.
Where the money comes from, and where it stops
The site may earn referral commissions if you join an ad network through a link on the networks pages. That funding model does not touch the editorial rules: thresholds and revenue shares are quoted only from each network's own published pages, quote-only vendors are labeled "not published" rather than guessed at, and no network pays for placement or ranking on this site. The comparison pages would read the same if the links earned nothing.