This is the Guardian.

Today, the world now contains 8 billion people.

Why does it matter?

And what does it look like from the country set to become the planet's most populous place?

The world is the most populous place in the world.

I'm here at New Delhi Railway Station, which is the main railway station in the city where I live.

If you really want to come and get a scale of the country as a whole,

of the millions of people that are on the move, of the diversity people that live here,

that work here, then this is an extremely good place to come.

Ahala Elisfeetason is the Guardian's South Asia correspondent.

There are families with young children, there are some young guys sitting having chai,

I'm seeing the man with what looks like 56 a prize filed up on one cart.

And the real kind of richness of India and that its population brings

is extremely evident here and kind of wonderful to be in the midst of.

But it also raises some big questions about the future of a city like Delhi,

which is due to expand by another 7-8 million people in the next 15 years.

Currently we're in the midst of pollution season to country where inequality is only getting worse

as the country develops and gets wealthier.

So you know how this city develops, how it adapts.

I think it's very crucial to how India can also harness the potential of its growing young

aspirational population and when I'm standing here in New Delhi railway station,

you know these are the questions of that I think face India as it becomes the world

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