This is a Litebite Book, a little more than 7,000 words long. The Great Famine which afflicted Ireland between 1846 and 1851 is perhaps the most studied, the most commented upon, the most reviled, and yet the most formative event in modern Irish History. Many books have been written about the famine, most recently The Famine Plot: England's Role in Ireland's Greatest Tragedy (2012) by Tim-Pat Coogan. What was the Famine? What caused it? Why did so many die, or leave if they could? I look at these questions beginning with a brief look at the background to the famine, chiefly the social and political state of Ireland before the famine hit, involving a brief outline of the Landlord and Tenant set-up and in particular the agricultural infrastructure. I then go on to describe the potato blight which was the direct cause, and examine its origins and effects. This leads to that much vexed and little understood topic, the reaction of the Government to the spectre of death by starvation of so many people - what they did to help, what they didn't do, and why. Was it nineteenth century genocide, as has been claimed? Was it beurocratic bungling? Or was the scale of this Act of God just too great for the machinery of Government at the time to recognise and address? I give my take on all this, and then I look at those notorious evictions, at the impact on the United States which was arguably to give birth to the bulk of the Irish American population there, and finally I comment on the long term impact on Ireland, how it was changed, and changed forever. Finally bear in mind that this is, deliberately, a short book, a summary if you like. My book on Daniel O'Connell, for example, is a little over 75,000 words. This one is just over 7,000. A LiteBite, in fact.