atmosphere

The earth's atmosphere is a about 700 km deep and is divided into five main layer according the way the temperature
changes with height. The lowest layer, the troposphere, contains over 75 percent of all the gases in the atmosphere
as well as vast amount of water trapped in clouds. Air movement within the layer produces weather in our planet.
Above the troposphere, stratosphere where air is thin and jet plane fly. there is mesosphere, thermosphere and,
exosphere. The ozone layer lies within the stratosphere, which provides protection from the Sun's harmful ultraviolet rays.
Radio signals transmit by bouncing off the ionosphere,a layer within the thermosphere that is made up of a
electrically charged(ionized) gas particles. Satelite are placed just below exosphere in upper thermosphere not in
space, but air is very thin where we canot breath.

SEO

SEO considers how search engines works, what people search for. Seo is simply a process to improve visibility of a website in a search engine. A higher ranked page are always on the top of the list in a search engine. SEO refers to Search engine optimizer. A consultant who carry out optimization projects on the behalf of the client.
Seo is the practice of improving and promoting a web site to increase number of visitors.link building service.Search engines are unique in that they provided targeted traffic - people looking for what you offer. Search engines are the roadways that makes this happen. If your site cannot be found by search engines or your content cannot be put into their databases, you miss out on incredible opportunities available to websites provided via search.

Aeroplane

When Wilbur and Orville Wright made their first flight with heavier than air machine on december 17, 1903, they shared an optimistic view of it's potential, saying "We believe that the aeroplane could play a major role in preventing war, because it would enable each side to know what the other was doing and and thus make it more difficult for either to gain an advantage". Their belief held true for about 10 years. Unarmed aircraft quickly became integral part of a contemporary warfare, but it's usefulness as a means of monitoring enemy activities led to development of a predator. An aircraft whose sole purpose was to destroy so the "fighter" was born. We have come a long way since Captain Coutelle used a balloon for aerial reconnaissance of enemy positions during
the battle of Fleurus in 1794. Nowadays a fighter can carry enough fire power to annihilate a city.