What is important?

In general one should be able to define and use the concepts in the course.

Chapter 1. Affine algebraic varieties.

Contents: algebraic sets, Noetherian rings, resultant, irreducible components, polynomial maps, regular functions, localisation of rings, rational maps, abstract affine varieties.
Theorems: Hilbert Basis Theorem (1.5), Nullstellensatz (1.11), decomposition in irreducible components (1.21), polynomial maps and ring homomorphisms (1.39), field of rational functions (1.49).

Chapter 2. Projective varieties.

Contents: projective space, homogeneous coordinates, irrelevant ideal, rational maps, Segre embedding, maps defined by linear systems, blow-up of a point.
Theorems: projective Nullstellensatz (2.14), projective closure (2.17).

Chapter 3. Projective plane curves.

Contents: Bezout, intersection multiplicity, inflection points, group law on cubic curve.
Theorems: Bezout's theorem (3.2), dimension of linear system of cubics (3.23), group law (3.29).

Chapter 4. Dimension.

Contents: dimension, integral extension, integral closure, going up and down, Noether normalisation.
Theorems: Characterisation of intergral extensions (4.6), Noether normalisation (4.26).

Chapter 5. Tangent space and nonsingularity.

Contents: tangent space, Jacobian criterion, Zariski tangent space, singular point.
Theorems: Intrinsic characterisation of tangent space (5.7), dimension of fibres (5.15).

Chapter 6. Lines on hypersurfaces.

Contents: Grassmann variety, Plücker coordinates, incidence correspondence, closewdness of image of projective varieties, 27 lines on a cubic surface and their configuration.
Theorems: every cubic surface contains a line (6.6), main theorem of elimination theory (6.7).

The numbers refer to the newest version of the notes.