Glossary
A plain-English dictionary of the health-tech terms you'll meet in these docs.
A quick reference for the jargon. Skim it, or search for a term.
Health & vitals
Vitals — core body measurements like heart rate, breathing rate, and temperature.
HRV (heart-rate variability) — the natural variation in time between heartbeats. More variation is generally a sign of a relaxed, adaptable nervous system.
PPG (photoplethysmography) — measuring blood-volume changes from how light interacts with your skin. A finger pulse oximeter is the classic example.
rPPG (remote PPG) — doing PPG from a distance with a camera instead of a contact sensor. The basis of AverScan.
TOI (transdermal optical imaging) — a research-grade rPPG technique used by AverScan's opt-in clinical scan mode.
SpO₂ — blood oxygen saturation, the percentage of oxygen your blood is carrying.
AI
LLM (large language model) — the kind of AI model that powers the conversational companion.
RAG (retrieval-augmented generation) — answering questions by first retrieving relevant passages from your documents, then generating an answer grounded in them. See The AI stack.
Embedding / vector — a list of numbers representing the meaning of a piece of text, so similar meanings sit close together and can be matched by concept.
Re-ranking — a second pass that reorders search results so the most relevant ones come first.
Tool calling — when the AI invokes a real capability (logging a meal, reading vitals) instead of only producing text.
Memory — durable facts the assistant keeps about you across conversations.
Streaming — sending an AI response token-by-token as it's produced, so it appears immediately.
Platform
Monorepo — one repository containing several apps and shared libraries. See Architecture.
API — the server interface every client (web, mobile, watch) calls to do work.
Webhook — a way for an outside service to notify AverCare when something happens (e.g. a build finished), verified with a signed secret.
Normalization — converting data from many devices into one consistent shape.
Two-way sync — changes flow in both directions; edit in either place and both stay current (as with Google Calendar).
Devices
HealthKit — Apple's shared health data store on iOS.
Health Connect — Android's equivalent shared health data store.
BLE (Bluetooth Low Energy) — the low-power wireless standard smart bands use to talk to your phone.
AverWatch — AverCare's own native Apple Watch and Wear OS apps.