Mostly the light that everyone experience on earth is from the sun.
People are too dependant on the light to live on. Light give out heat.
Without light our earth would feel cold, damp, and dark including huan.
People can fo a lot of thing with the help of sun like cooking or drying clothes,
which help in our daily life. Light is like god, which give living things life.
People invented torch from the inspiration of the sun. Let look at the detail of sun and other light source:
The Sun
The Sun is the star at the centre of the solar system.
The Earth and other matter including other planets, asteriods,
meteroids, comets and dust orbit around the Sun,
which by itself accounts for about 99.8% of the solar system's mass.
Energy in the form of light suppot most life on earth via photosynthesis
and drives Earth's climate and weather.
Although the Sun appears white but actually is a combination of seven colours.
The Star
A star is massive, luminous ball of plasma(ionized gas) stars from together
to form galaxies(massive, gravitationally bound system consisting of stars)
and they dominate the visible universal. The nearest star to Earth is the Sun,
which is the source of most of the energy of the Earth, including daylight.
Other stars are visible in the night sky, when they are not outshone by the Sun.
A star shines because nuclear fusion in its core releases energy which traverses
the stars; intend then radiates into outer spaces. Without stars,
life and most atomic element present in the Universe would not exist.
The incandescent light bulb
The incandescent light bulb is the source of artificial light that works by
incandescent, an electrical current passes through a thin filament,
heating it and causing it to be become excited, releasing thermally equilibrated
photons in the process. The enclosing glass bulb prevents the oxygen in the air
from reaching the hot filament, which otherwise would be destroy
rapidly by oxidation.A benefit of the incandescent bulbs is that they can
produce a wide range of voltages, from just a few volts up to several thousand volts.
Because of their poor luminous efficacy, incandescent light bulbs are gradually
being replaced in many applications by (compact) fluorenscent lights, high-intensity
discharge lamps.