Infrared means a type of invisible electromagnetic radiation with wavelengths longer than visible red light but shorter than microwaves, often associated with heat.

Basic meaning

  • Infrared literally means “below red,” from Latin “infra,” because it sits just beyond the red end of the visible light spectrum.
  • It covers radiation with wavelengths from about 700 nanometers up to about 1 millimeter, which is longer than visible light but shorter than microwaves.
  • Human eyes cannot see infrared, but skin can often feel it as warmth from things like the Sun, fire, or a heater.

Infrared as “heat”

  • Any object warmer than absolute zero gives off some infrared radiation, which is why infrared is strongly linked with heat.
  • A lot of the “thermal” energy from room‑temperature surfaces and our bodies is emitted mainly in the infrared range.
  • Devices like thermal cameras and night‑vision scopes detect this infrared radiation and convert it into images showing hot and cold areas.

Everyday uses

  • Remote controls for TVs and other gadgets send coded infrared light signals to tell devices what to do.
  • Infrared heaters and lamps use this radiation to warm people, food, or industrial materials efficiently.
  • Scientists use infrared spectroscopy to identify chemicals by how they absorb or emit infrared light at different wavelengths.

Where it fits in the spectrum

  • Infrared is one part of the electromagnetic spectrum, between visible light and microwaves, in the sequence gamma rays → X‑rays → ultraviolet → visible → infrared → microwaves → radio waves.
  • The infrared band itself is often split into near, mid, and far infrared, with near‑infrared closer to visible light and far‑infrared closer to microwaves and more strongly felt as heat.

Mini story to picture it

  • Imagine a rainbow stretched out on a wall; you see violet through to red, but just past the red edge—where your eyes see nothing—a thermometer would quietly climb higher.
  • That “hot but invisible” region past red is where infrared lives, carrying energy your skin can feel even though your eyes cannot see it.

Information gathered from public forums or data available on the internet and portrayed here.