1 INTRODUCTION  
2 DIVERSITY IN SEARCH  
3 DIVERSITY IN RECOMMENDATION  
4 NOTATIONS  
5 METRICS OF DIVERSITY IN SEARCH AND RECOMMENDATION  
6 OFFLINE APPROACHES FOR ENHANCING DIVERSITY  
7 ONLINE APPROACHES FOR DIVERSITY  
8 APPLICABILITY OF DIVERSITY METRICS AND APPROACHES  
9 OPENNESS AND FUTURE DIRECTIONS  
10 CONCLUSION