In this book, you will find a number of styles of text that distinguish between different kinds of information. Here are some examples of these styles, and an explanation of their meaning.

Code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles are shown as follows:

"The acf function will plot the correlation between all pairs of data points with lagged values."

A block of code is set as follows:

> install.packages("forecast") 
> require(forecast) 
> forecast(my_series, 4) 

New terms and important words are shown in bold. Words that you see on the screen, in menus or dialog boxes for example, appear in the text like this: "Click on Download R for Windows, as shown in the following screenshot."