An excellent text book but needs a bit of updating now as it was written about ten years ago. However none of the "basic" physics is affected. targeted at final year undergraduates/ postgraduates. Packs in a lot. Assumes a good working background knowledge of Physics and Maths but not an unreasonably high one.
Like all books in this series the worked examples are excellent and to the point. However the teaching style was not as good as 'Relativity Black holes and Cosmology'. It is nevertheless an excellent intoduction to this subject.