I think this is a great book that provides not only a great introduction to string theory (there is no assumed prior knowledge of string theory), but also provides coverage of many more advanced topics as well. I think it's likely that the vast majority of students specializing in string theory will want to read it at some point in their studies.<br><br>The coverage of topics in the first few chapters is in some ways fairly standard. The first two chapters consists of a high level overview of string theory, bosonic string, the Nambu-Goto action the Polyakov action, the Virasoro algebra, the critical dimension, light code gauge and the spectra of open/closed strings. After this there is a chapter on conformal field theory, naturally emphasizing the parts relevant to string theory (including a bit of string field theory). This is followed by discussions of worldsheet supersymmetry, spacetime supersymmetry, anomalies, T-duality and heterotic strings. The writing is very clear and considering the nature of the material, fairly straight forward. There are two things that I considered exceptional strengths. One is that the discussions incorporate D-branes, M-theory and the (unexpected) symmetries of string theory early on. The other is that there are numerous worked examples, as there are throughout the book.<br><br>At a very high level the rest of the book contains more extensive discussions of M-theory, compactification (including a substantial amount besides the standard approach of the compact dimensions being a Calabi-Yau space), mirror symmetry, S-duality, possible cosmological consequences of string theory, black holes and other solutions with horizons, matrix theory, AdS/CFT correspondence (a proposed equivalence between closed string solutions on the product of a sphere and anti-deSitter space and Yang-Mills theories) and the holographic principle (or as some would say conjecture).<br><br>The things I appreciated the most about this material was that is was a very interesting mix of topics. The discussion of black holes and cosmology was fairly extensive (for cosmology it was the most extensive I've seen in a text book). As was the coverage of the AdS/CFT correspondence. There were also some topics that I don't recall seeing in other string theory books, such as warped geometries in compactification and S-branes (these are like D-branes but they satisfy Dirichlet boundary conditions in timelike directions).<br><br>Needless to say it's a fairly advanced book. There is some coverage of things like complex spaces, topology, general relativity and cosmology. However this material is more along the lines of a review, not something intended to teach from first principles (some of the other string theory books cover this kind material in more detail).<br><br>All-in-all I believe this book not only provides a great introduction, it also provides an excellent treatment of some of the more advanced topics in string theory.