i donot understand what is atmosphere

Answer 1

http://www.kidsgeo.com/geography-for-kids/0040-introduction-to-our-atmosphere.php

Answer 2

There are several meanings for atmosphere. Here are several of them. Pick the one that fits your case.
http://www.google.com/search?hl=en&client=firefox-a&rls=org.mozilla:en-US:official&hs=5AB&defl=en&q=define:atmosphere&sa=X&oi=glossary_definition&ct=title

Answer 3

atmophere is the air surronding the earth. k