1. Welcome to Linux

In This Chapter

Ubuntu Linux 2 The History of UNIX and GNU–Linux 3 The Heritage of Linux: UNIX 3 What Is So Good About Linux? 6 Overview of Linux 12 Additional Features of Linux 17 Conventions Used in This Book 19

An operating system is the low-level software that schedules tasks, allocates storage, and handles the interfaces to peripheral hard-ware, such as printers, disk drives, the screen, keyboard, and mouse. An operating system has two main parts: the kernel and the system programs. The kernel allocates machine resources—including memory, disk space, and CPU (page 1143) cycles—to all other programs that run on the computer. The system programs include device drivers, libraries, utility programs, shells (command interpreters), configuration scripts and files, application programs, servers, and documentation. They perform higher-level housekeeping tasks, often acting as servers in a client/server relationship. Many of the libraries, servers, and utility programs were written by the GNU Project, which is discussed shortly.