The difference of world climate and weather?

I am from Hong Kong, and the temperature is in summer time here, and I have an Australian friend living in her winter time, but don't believe that I am in summer time ( I know Australia New Zealand the southern hemisphere were the winter time because of the SUN movement) because she expecting we are all living at the same Hemisphere line, and I tried to explain that we are at different zone of the planet, so as to find the supporting information to tell her, the planet should be somewhere is hot, hotter, somewhere cold and colder... etc the differences, well despite of north and south pole were the all known coldest places on the earth, so I am looking for some supportive information, link, or on the wikipedia information to show her that in one page to prove our planet with different temperature zone around the world and so.

BIG Thank you!