In this book, you will find a number of text styles 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: "Start Wireshark by clicking on the Wireshark icon or type Wireshark in the command line."

Any command-line input or output is written as follows:

[bash ~]# cat /proc/sys/net/ipv4/tcp_fin_timeout 60

New terms and important words are shown in bold. Words that you see on the screen, for example, in menus or dialog boxes, appear in the text like this: "Click on Interface List; Wireshark will show a list of available network interfaces in the system."