Relative humidity and is expressed as a percentage.
Absolute humidity is expressed as a concentration - mg/L.
Specific humidity is a ratio of masses - water to air in a finite volume.
Humidity meters are used to measure the humidity outside. Typically, these would be placed on the outside of your house to accurately measure the humidity.
With a Humidity measuring device
To measure humidity you need a hygrometer. It is a tool that measures the amount of moisture in the air.
Humidity
A small inexpensive instrument for measuring humidity is called a Hygrometer (sometimes they are also called relative humidity indicator or humidity sensor). These instruments measure humidity.
Relative humidity
2 instruments are required to accomplish these measurements:a barometer to measure atmospheric pressure.a hygrometer to measure humidity.
A device used to measure humidity is called a psychrometer or hygrometer.
Humidity
Humidity refers to the degree of wetness of the atmosphere. By using a humidity gauge or sling psychometer, humidity in the backyard can be measured.
Like in a Hygrometer to measure humidity you use percentage (%)
There is no such thing as a sygrometer, but a hygrometer is a device that is used to measure the humidity of the air. It can indicate relative humidity or absolute humidity.