There are a number of text conventions used throughout this book.

CodeInText: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: "The ggplot2 package is the most commonly used visualization package in R."

A block of code is set as follows:

life <- fread("ch1_life_exp.csv", header=T)

# View contents of life
head(life)

Bold: Indicates a new term, an important word, or words that you see on screen. For example, words in menus or dialog boxes appear in the text like this. Here is an example: "After logging in, search for the topic Cost Management + Billing in the left-hand menu, as shown in the following screenshot."