Uladzislau Bayouski

Hold your phone perfectly still. Even doing nothing, it knows which way up it is, how bright the room is, how close your face is, and what the air pressure is doing — a dozen tiny devices measuring the physical world thousands of times a second. Every connected device starts exactly there. Strip away the cloud, the dashboards, the machine learning: IoT makes one simple promise — something, somewhere, is measuring something real. Take the sensors away and the Internet of Things is just the Internet. Yet sensors are the part every tutorial sprints past. "Wire the DHT22 to pin 4" — with no word on what the thing actually is, why its readings wobble, or why two identical modules disagree by two degrees. This is Sensors 101: what they are, how they talk, which families matter, and what the datasheet really means. 👁️ The Short Version A sensor is a transducer — it converts physics (heat, light, motion, chemistry) into an electrical signal. The mental model that actually works...

In a utility cupboard somewhere in Manchester, a gas meter fitted in 2015 is still sending a reading every night. Same battery. Nobody has opened the case. Meanwhile, the ESP32 sensor you built last weekend — the one on the windowsill reporting temperature to a dashboard — is dead. Three days on two AA cells. The two devices aren't as different as they look. Both are a microcontroller, a sensor and a radio. Both wake up, take a measurement, send a few bytes and go back to sleep. The difference between three days and fifteen years isn't a better battery — it's what the device does with the 99.8% of its life when nothing is happening. That's what power management in IoT actually is: not a component you buy, but a set of decisions about sleeping, waking and talking. 🔋 The Short Version Every battery-life question comes down to one division: capacity divided by average current. A pair of AA lithium cells holds about 3,000 mAh. Draw 3 mA on average and you get six week...

You've decided to build something connected. You've heard two names more than any others:  Arduino  and  Raspberry Pi . Both are affordable. Both are beginner-friendly. Both show up in every "getting started with IoT" article on the internet. But they are fundamentally different tools — and picking the wrong one can cost you time, money, and a weekend of frustration. The Short Version Arduino is a microcontroller. It does one thing at a time, does it reliably, and does it with almost no power. Perfect for reading sensors, controlling outputs, and anything that needs precise real-time timing. Raspberry Pi is a full single-board computer. It runs a full OS, supports Python and JavaScript out of the box, and handles complex tasks like data processing, networking, and even machine learning. The quick breakdown: Programming : Arduino uses C/C++ via its own IDE — lightweight, real-time. Raspberry Pi supports Python, JS, C++ and more — feels like coding on a regular compu...