Less than a dollar a day is a phrase we are all familiar with, but what does it really mean?
Almost half the world's population lives on less than a dollar a day, but the statistic fails to capture the humiliation, powerlessness and brutal hardship that is the daily lot of the world's poor.
In this series, Mike Wooldridge looks at what it's really like to have to live on a dollar a day and how it can mean different things in different countries, and asks whether the global target of halving world poverty by 2015 can really be achieved.
It isn't all about desperation and gloom, though: Mike meets people of incredible energy and determination, living in vibrant communities and having a diversity of experiences.
At 15, Dzifa Adjanu said she wanted to become an accountant so that she "wouldn't get cheated in life".
Fifteen years on, this determined young Ghanaian has achieved her ambition, although it has been an enormous struggle for her family to find the money to complete her education.
Education, and in particular girls' education is one of the Millennium Development goals for halving global poverty by the year 2015, and Ghana is one of the few African countries on track to meet the target of getting more girls into school - but the challenges are still enormous.
Mike Wooldridge goes with Dzifa back to her old school in Ghana's Volta region, and meets her mother Margaret, who sacrificed so much to get her through. He also meets other girls who have not been so fortunate as Dzifa and have had to drop out of school due to financial problems.
A Dollar A Day