Now, in the first years of the twenty-first century, we understand with reasonable confidence and in reasonable detail many of the processes that led to our existence on Earth. We understand much about how galaxies, stars and planetary systems form. We have a theory that explains much about how the Universe has developed since the Big Bang (although it does not explain why the Universe exists). We understand many of the processes of life: how lifeforms obtain and use energy, how they maintain themselves, how they reproduce. We have Darwin's theory that explains how different species arise. But we don't understand how life started.
What makes this problem particularly interesting now is that we have the knowledge and tools to make progress towards finding an explanation. We have detailed knowledge of physics, chemistry and biology that was not available to earlier generations. We have the technical means to carry out experiments, both 'in vitro' and in computers.
I have included a section outlining the problem and its recent background, a section on landmark developments in the twentieth century, and a section discussing the major issues relevant to the problem of the Origin of Life.
The Origin of Life is a huge area, and clearly the topics I have chosen to cover reflect to some degree my own viewpoint. Put briefly, I believe that metabolic processes played an important role in the processes that led to the Origin of Life, either as the key mechanism or as one of the key mechanisms.