This is undoubtedly the best book for an advanced introduction to Macroeconomics at graduate level, before one takes up more technical macro/growth theory books like Romer, Obsfield or Barro etc. It approaches the subject 'macro school' wise, ie by taking a historical and chronological methodology which makes the subject much more interesting, providing a clear conceptual background of the development of macroeconomics as a separate field in past 70-80 years. Starting from Keynes, it discusses all the major development, concepts, theory, models and their interrelationships in macroeconomics today including the recent spurt in growth theory analysis.
It is a must read not only for any budding economists but also for well informed general readers interested in economics as a whole.