1. Introduction

2. Observations and Data Reduction

3. Selection and Classification of RR Lyr Stars

4. The OGLE Collection of Galactic RR Lyr Stars
4.1. Spatial Distribution
4.2. Magnitude Distribution

5. Completeness and Cross-Check with Other Catalogs

6. RR Lyr Stars in Globular Clusters

7. Multimode RR Lyr Stars

8. Conclusions