Your thermometer says 21.4, your scale says 68.3, and your air monitor says the room is fine. But how far should you believe any of them? This book explains, in plain language and with simple worked arithmetic, what sits behind every sensor reading: accuracy, precision, resolution, noise, drift, calibration, sampling lag and uncertainty. You will learn to run calibration checks at home with melting ice, check weights and a salt box, to tell a real change from random wobble, and to read a specification sheet without being misled. Practical chapters apply the ideas to temperature and humidity sensors, air quality monitors, scales, fitness trackers and smart-home devices, so you can trust each number exactly as much as it deserves.



Imad Muratspahic is an independent author of practical how-to guides, technical handbooks, history and fiction. The books aim to be clear, honest and useful from the first page.