The earth is the planet we all live on. It surrounds the sun, from which it receives most of the heat energy in the form of sunlight, within one year (365 days).
The earth's atmosphere
makes it a place which allows life and the existence of mankind. Atmospheric conditions are different all over the world. These differences are called climate
, and make the living conditions for life very different (from "nice" over "hard" to "hostile") on different parts of the earth.
The atmosphere conditions do also often change daily. These daily changes are called weather
and are the outside conditions which we feel more immediately. That's why we often talk about the weather.