Field Guide · hardware

Also known as: Wearable

A wearable computer is a small computing device worn on the body — on the wrist, head, ear, or clothing — built to provide hands-free, always-available computing.1

smart glasses (head) hearable (ear) smartwatch (wrist) fitness band / clip (body)
Wearables are grouped by where they sit on the body — glasses on the head, hearables at the ear, a smartwatch on the wrist, a band or clip on the torso — each a small sensor-and-radio package under tight size and battery limits.

Overview

Wearables span smartwatches and fitness bands, smart glasses and AR headsets, and “hearables” such as smart earbuds. All share the same constraints: a tiny SoC, a small or absent display, low-power radios like Bluetooth and NFC, and a battery measured in fractions of a phone’s.

Many lean on a paired smartphone for heavy lifting and connectivity, acting as a sensor-rich satellite rather than a standalone computer. The design pressure is relentless: every added feature costs volume, weight, and battery on a device that must be comfortable to wear all day, so wearables sense and relay far more than they compute.

Wearable form factors

The category spans several body positions, each suited to different jobs:

Form Worn on Typical job
Smartwatch Wrist Notify, sensors, apps
Fitness band Wrist Step & heart tracking
Smart glasses Head Display, camera, AR
Hearable Ear Audio, voice assistant
Smart clothing Body Biometrics, motion

What unites them is not a screen or a chip but the fact of being worn — placement on the body is the defining trait.

Where it fits

The category is defined by being on the body rather than in a pocket, which favors continuous sensing — motion, heart rate, location via GPS — over raw performance. The extreme size and power limits make wearables the most constrained tier of personal computing, suited to capturing and relaying data, not to running compute-heavy workloads like an SDR decode pipeline on their own.

Sources

  1. Wearable computer — Wikipedia, on body-worn computing devices and their forms. 

See also