ada: This is used for stochastic boosting

caret: This is used for classification and regression testing

class: This package has classification functions

clue: This package has the cluster ensemble methods

e1071: This package has miscellaneous functions for the statistics department

kernlab: This has kernel-based machine learning methods

MASS: This stands for Modern Applied Statistics with S

neuralnet: This has artificial neural net support

randomForest: This has random forests for classification

relaimpo: This package has functions to determine the relative importance of regressors in linear models