Everything we now know about Covid-19One of the challenges for understanding Covid-19 is that all the science has happened under a spotlight.
Usually, by the time you read about scientific research on a news site like the BBC, it has gone through a period of scrutiny, development and evaluation.
That science is not secret as it's being done, it's just something people rarely pay attention to until it reaches a journal.
What's different about Covid-19 is that we all – the public, politicians, journalists – have experienced science at its frontiers.
At the border between the known and the unknown, research is messy, confusing, and sometimes contradictory.
Human fallibility and bias is possible. But this is how it works. This is how we find out how the world operates, and how we move forward to greater understanding as a species.
Over the past year, BBC Future has aimed to go deeper into the science behind the pandemic as it evolved. What have we learnt, and what is still unknown?