Here is a list of useful libraries (that will grow over time)
Making plots
library(Corrplot) #to make nice correlations plots with values inside
library(ggplot2) #a must have for pretty graph, but can do without
library(reshape2) #sometimes needed to reshape data to plot with ggplot2
Data cleaning
library(Amelia) #to visualize missing data
Data input
library(readxl) #faster than read.xlsx for reading Excel files
Data manipulation
library(dplyr) #what made me use R, makes data manipulation more human
librar(plyr) #use it for merging data, simpler than dplyr on that one
Data statistics
library(moments) #to get ... moments
library(e1071) #to get skew and kurtosis and other stats from distribution
library(nortest) #to easily test normality
Programming
library(purr) #to use among other the map function to replace for loops
Performance for binary classification methods
library(InformationValue) #Get KS, AUROC, SomersD, confusionMatrix etc.. faster
