I recommend this book to everyone who wishes to understand (or at least begin to do so) the 20th century... In my opinion, that is an imperative, because if we don't understand our past, we won't be able to see our present clearly, and we will also be deprived from a good perspective regarding our future. As Hobsbwam says, things "can only be understood as part of a particular historical context".
In "The Age of Extremes", Hobsbawm's explains us his idea that the 20th century began in 1914 (with the outbreak of World WarI), and ended in 1991 (with the collapse of the USSR). That is the reason why he calls it "the short century". He divides that "short century" in three parts: an age of catastrophe (from 1914 to the end of World War II), a golden age (1947 - 1973) and the Landslide (1973 - 1991).
Hobsbawm not only delves into politics, but also into economics, technology, and art, all with a profound knowledge of the subject and a caustic wit that I find irresistible.
Yes, of course that there are a lot of history books regarding the 20th century. As a matter of fact, I've read many of them... But this is still my favorite, because it manages to both interesting and clear, entertaining and useful
On the whole, highly recommended :)