How does XGBoost work for classification?

Related questions

1. Why is the decision forest better than the random forest?
2. Is XGBoost tree based?
3. What is N_estimators in random forest?
4. What is Nthread in XGBoost?
5. Is Random Forest an ensemble method?
6. What is the difference between GBM and XGBoost?
7. How does XGBoost algorithm work?
8. Is Random Forest good for regression?

Tags

1. #xgboost
2. #minimize
3. #supports
4. #modeling
5. #models
6. #boosting
7. #implements
8. #called
9. #algorithm
10. #descent
11. #adding
12. #problems
13. #gradient
14. #library
15. #because
16. #approach
17. #regression
18. #classification
19. #predictive
20. #decision