What is a capacitive humidity sensor?

A capacitive humidity sensor measures relative humidity by detecting changes in capacitance of a moisture-sensitive dielectric material.

DHT11 Digital Temperature and Capacitive Humidity Sensor, 3-5VDC

A capacitive soil humidity sensor: Part 4 – Arduino, ESP8266

Humidity Sensor - Types and Working Principle - ElectronicsHub

A nanoforest-based humidity sensor for respiration monitoring

Vaisala HUMICAP® Technology

Soil Humidity Sensor Capacitive SEN0193 - SmartbitBN- The Bruneian

Humidity Sensor Types

Succession model for soil moisture module (hygrometer). No adjustable switching contacts, works analogously and shows so precisely moisture values

Soil Moisture Sensor Hygrometer Module V1.2 capacitive compatible with Arduino and Raspberry Pi

Maker Soil Moisture Sensor (Capacitive)

Humidity Academy Theory 6 – The Capacitive Sensor