In the second edition, the entire book has been revised, with a view to eliminating errors, incorporating suggestions of readers, updating concepts, and discarding material that is no longer relevant. In this way, the book has been kept concise while remaining as up-to-date and accurate as possible. In keeping with the current trend of postgraduate entrance examinations, all topics are updated. Key points and comparisons are given in boxes for greater emphasis. In shaping and revising this latest edition, we have committed ourselves to making the manual an invaluable resource for students.