CW ComplexesCovers the construction and properties of CW complexes, including weak topology and characteristic maps.
Lifting CriterionExplores the lifting criterion for maps between path-connected and locally path-connected spaces.
Homotopy Extension PropertyDemonstrates how to obtain homotopy equivalences between different spaces using the homotopy extension property.
Dimension theory of ringsCovers the dimension theory of rings, including additivity of dimension and height, Krull's Hauptidealsatz, and the height of general complete intersections.
Sheaves: Hartshorne I.1Covers the concept of sheaves, emphasizing the unique determination of functions by local data and the importance of direct limits.