The conflict between Armenia and Azerbaijan is over, but some are still waiting for news of missing relatives.

Collector William Fagan finds 70-year-old photographs in a camera.

Five challenges of distributing a Covid-19 vaccine to billions of people.

The campaign to save a 100-year-old tree shows cultural fears can make politicians listen in Kenya.

The toxic fumes from stubble burning affects hundreds of millions - but curbs to stop it keep failing.

Machine learning is helping firms across many industries more quickly solve difficult challenges.

The founders of the Black Lives Matter movement tell the BBC's 100 Women season they are optimistic.

Calabria was not hit by the first wave of the pandemic but its fragile health system is buckling now.

The two nations had expelled each other's envoys over a historical dispute dating back a century.

Authorities are trying to establish if there was negligence in the treatment of the Argentine star.