In this book we cover different subjects related to the Linux world. First, in Chapter 1, we talk about the virtualization software VirtualBox. In this chapter we show how to obtain the program and how to install and configure a virtual machine. We also show how to obtain the Debian GNU/Linux operating system. Chapter 2 explores the installation of operating systems for servers. We show how to install Debian in the context of server use. Besides step-by-step installation, we provide hints on which partitions can be created in the partition table. Chapter 3 gives a basic introduction to Linux commands and Shell Script programming. It is hoped that by reading this book the reader will be able to minimally explore the Linux universe, from installation to day-to-day use.