library
{base}
Load an R package
colnames
{base}
Retrieve column names of a data frame
attach
{base}
Attach Set of R Objects to Search Path
summary
{base}
Obtain summary statistics or detailed regression output
read.csv
{utils}
Read a csv file to data frame. Specify stringsAsFactors = FALSE to keep all string columns as characters
setwd
{base}
Set Working Directory
c
{base}
Combine values/vectors into a vector
lm
{base}
Fit a linear model
The end!