CONTENTS
Introduction 1
1. Elementar y propertie s o f polynomia l ring s 2
2. Affin e space s and projective space s 5
3. Rule d surface s an d rationa l surface s 1
4. Automorphis m group s o f polynomia l ring s 15
5. Cremon a group s 17
6. Grou p action s o n affin e ring s 2
7. Complet e reducibilit y o f rationa l representation s 2 3
8. Ring s of invariants 2 5
9. Som e remark s o n orbit s 3 0
References 3 2
