Move money from your bank to a stranger's bank and it arrives in seconds. Switch doctors across the street and your records arrive by fax, by CD, or not at all. Same you, same decade. The difference isn't technology — banking and healthcare both run on computers. The difference is that banks agreed on a shared language for moving information, and healthcare mostly hadn't.

FHIR (say it like "fire" — Fast Healthcare Interoperability Resources) is healthcare's version of that shared language. Instead of every hospital, insurer, and app inventing its own file formats, FHIR defines standard building blocks — a Patient looks like this, a Coverage (your insurance) looks like this, a Claim looks like this — and a standard way to ask for them over the internet, the same way apps already talk to each other everywhere else.

Two things make this more than a tech-industry hobby. First, it's the law now: US regulations require insurers and hospitals to expose your data through FHIR so you can pull your own records into an app you choose, and so your new doctor or new insurer can get your history without you playing courier. Second, it attacks the paperwork war between doctors and insurers — prior authorizations, documentation requests, the stuff that delays your care — by letting those systems talk directly instead of by fax and phone tree.

ImOnFHIR is a lab for exactly that second part: building and testing how insurers and providers exchange this data, using realistic-but-fake patients, so the plumbing works before real people depend on it.

Want to go deeper? The next card explains the specific laws and deadlines pushing insurers to do this now — or jump to the builder's field guide if you want to see the machinery.