Most populated cities.

Tokyo (Japan) is the world's most populated city followed by Mexico City (Mexico) and New York (USA) in 2nd and 3rd places.

Largest dwelling

The Sultan's palace (in Brunei) has 1788 rooms and 257 lavatories making it the world's largest dwelling. 

Largest food chain.

McDonalds, USA, is the world's largest food chain with more than 30000 restaurants in 100 countries and serve more than 46 million customers every day.The biggest and the busiest outlet is in Moscow (Russia).

Countries

The world comprises 193 independent countries and 60 dependencies.

Population

It is estimated that the Indian population of 1.1 billion in 2005 will increase to 1.4 billion by 2025, and will surpass China's population by 2030. China will be contained to 1.45 billion by 2050, but India will have 1.6 billion by 2050. The world population will increase from 6.5 billion to 9 billion.

I don't think its good !!

Busiest airport

O'Hare International Airport, Chicago (USA), is the busiest airport in the world. On an average, there is a take off or landing every 36 seconds.
36 SECONDS!!!!!!

World's largest dwelling.

With 1788 rooms and 257 lavatories, the Sultan's palace in Brunei is the largest dwelling in the world.
Fancy having a house that big.

World's costliest cities.

Tokyo, Osaka and Kobe (Japan), followed by Paris (France), Oslo (Norway), Copenhagen (Denmark) and London (UK) are the world's costliest cities to live in .
Check your bank balance before shifting in any of these cities !!

World's highest mountain.

Hawaii's Mauna Kea is the world's highest mountain, measured from its base,which rises to a height of 9,500 m from sea level. It is an ancient dormant volcano and is half submerged in the Pacific Ocean.
I always thought it was Mt. Everest.