Infrared radiation is used in industrial, scientific, and medical applications. Night-vision devices using active near-infrared illumination allow people or animals to be observed without the observer being detected. Infrared astronomy uses sensor-equipped telescopes to penetrate dusty regions of space, such as molecular clouds; detect objects such as planets, and to view highly red-shifted objects from the early days of the universe. Infrared thermal-imaging cameras are used to detect heat loss in insulated systems, to observe changing blood flow in the skin, and to detect overheating of electrical apparatus. 

The onset of infrared is defined (according to different standards) at various values typically between 700 nm and 800 nm, but the boundary between visible and infrared light is not precisely defined. The human eye is markedly less sensitive to light above 700 nm wavelength, so longer wavelengths make insignificant contributions to scenes illuminated by common light sources. However, particularly intense near-IR light (e.g., from IR lasers, IR LED sources, or from bright daylight with the visible light removed by colored gels) can be detected up to approximately 780 nm, and will be perceived as red light. Sources providing wavelengths as long as 1050 nm can be seen as a dull red glow in intense sources, causing some difficulty in near-IR illumination of scenes in the dark (usually this practical problem is solved by indirect illumination). Leaves are particularly bright in the near IR, and if all visible light leaks from around an IR-filter are blocked, and the eye is given a moment to adjust to the extremely dim image coming through a visually opaque IR-passing photographic filter, it is possible to see the Wood effect that consists of IR-glowing foliage.
What is used in various ways?
How many ways is it used?
What are the general ways it is applied?
What helps you not be noticed at night?
What does it use?
Is the point of visibility exactly known?
What is the general range?
Where does the eyeball become not as perceptive?
Do astronomers use it?
For what?
Like what?
Can it be helpful with medical stuff?
How so?
How can it help an electricity unit?
How wide can the waves be and still be noticed?
When is it hard to notice?
How can hard to notice things be fixed?
What is brighter than most things when noticed?
Can an eyeball be adjusted for this?
What is the outcome of this observation called?
Infrared radiation
Infrared radiation is used in industrial, scientific, and medical applications.
a lot
Infrared radiation is used in industrial, scientific, and medical applications. Night-vision devices using active near-infrared illumination allow people or animals to be observed without the observer being detected. Infrared astronomy uses sensor-equipped telescopes to penetrate dusty regions of space, such as molecular clouds; detect objects such as planets, and to view highly red-shifted objects from the early days of the universe. Infrared thermal-imaging cameras are used to detect heat loss in insulated systems, to observe changing blood flow in the skin, and to detect overheating of electrical apparatus. 

industrial, scientific, and medical
Infrared radiation is used in industrial, scientific, and medical applications
Night-vision devices
 Night-vision devices using active near-infrared illumination allow people or animals to be observed without the observer being detected
active near-infrared illumination
Night-vision devices using active near-infrared illumination
no
the boundary between visible and infrared light is not precisely defined. 
between 700 nm and 800 nm,
The onset of infrared is defined (according to different standards) at various values typically between 700 nm and 800 nm,
above 700 nm wavelength
human eye is markedly less sensitive to light above 700 nm wavelength
yes
 Infrared astronomy uses sensor-equipped telescopes to penetrate dusty regions of space
to penetrate dusty regions of space
Infrared astronomy uses sensor-equipped telescopes to penetrate dusty regions of space
molecular clouds
such as molecular clouds
yes
Infrared radiation is used in industrial, scientific, and medical applications.
to observe blood flow
to observe changing blood flow in the skin
detect overheating
detect overheating of electrical apparatus
780 nm
 can be detected up to approximately 780 nm
above 700 nm wavelength
The human eye is markedly less sensitive to light above 700 nm wavelength
by indirect illumination
(usually this practical problem is solved by indirect illumination
Leaves
Leaves are particularly bright in the near IR, and if all visible light leaks from around an IR-filter are blocked
yes
the eye is given a moment to adjust 
the wood effect
, it is possible to see the Wood effect that consists of IR-glowing foliage.