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: "There are two functions in the spi-dev library for sending the data to SPI slave devices."

A block of code is set as follows:

import RPi.GPIO as GPIO
from time import sleep
GPIO.setmode(GPIO.BCM)
GPIO.setup(17, GPIO.OUT)
Print "All Set in Python! Let's Blink"

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

sudo nano /etc/modprobe.d/raspi-blacklist.conf

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: "Select the Enable Camera option in the configuration settings using the keyboard."