Chapter 6 – Introduction to Ubuntu Linux

The Unix operating system developed at the AT&T Bell Laboratories in 1969 has become a turning point in the operating system development scenario. The key persons involved in this development were Ken Thompson, Dennis Ritchie, Brian Kernighan, Duglas McIlroy and Joe Ossanna.

The people who developed Unix were originally working on a joint project with General Electric (GE) and Massachusetts Institute of Technology (MIT) to develop a large ambitious multiuser operating system called Multics (Multiplexed Information and Computing Service). Though the project had many innovations to its credit, it was a large and unwieldy project that was not progressing as expected. When AT&T decided to pull out of the project, Thomson, Ritchie and others decided to develop a smaller operating system to keep alive some of the ideas of Multics. Ken Thomson had developed a game called Space Travel while still on the Multics project, but it was too expensive to run the game on a large machine in active use. He found a little used machine at Bell Labs and redeveloped Space Travel to run on it.

Unix also provided a very powerful command line environment that supported combining the power of existing commands in flexible ways to get a new job done

Linux
Linux, just like its predecessor Unix, is known for its high performance, security, reliability and portability. No matter how old or low-end the hardware is, one can find a Linux distribution that would run on it. It is quite stable on most PC configurations. It combines the high-power CLI that has traditionally been Unix’s strength with an impressive GUI that makes it almost as user-friendly as the other two OSs. Linux has a particularly strong presence in the Netbook (small notebook computer used primarily to access the Internet) category.

A major advantage of Linux is that not only is it free; it also provides us complete freedom in running the operating system. Linux provides excellent interoperability with Microsoft Windows and you can access the Windows partitions on your computer and the organization’s Microsoft Windows servers as easily as from Windows.Linux meets all the basic needs of an average computer user and, once you settle down, can be as comfortable to use as it can get. And all this is yours, 100% free and 100% legal.

Ubuntu has a fixed release cycle, with a new version being released in the April and October months of each year. The release numbers are denoted by two-digit year, followed by a dot, followed by two-digit month. Thus, Ubuntu 10.04 LTS was released in April 2010.

Basic Concepts of Ubuntu Linux To use Ubuntu on a regular basis, one needs to install Ubuntu. Usually, installing a new operating system requires that a separate partition on the disk be made available for exclusive use by that OS. The installation procedure involves formatting the partition and creating a new file system on it.

The file system can be unmounted by clicking on this icon. It may be mounted again when the user tries to access it again next time. The root file system cannot be unmounted. Removable devices are automatically mounted when they are inserted. Read-only media like optical disks can be unmounted by simply removing or ejecting them. Media on which writing is possible (like USB flash disks) must be unmounted by clicking the unmount icon in the file browser or by right clicking its icon on the desktop and selecting “safely remove device” option.

Linux provides us with multiple virtual screens to work with. In fact, we have access to 12 different virtual screens altogether. These can be accessed by pressing the shortcut keys CTRL+ALT+F1, CTRL+ALT+F2, CTRL+ALT+F3, etc. The first six of these screens are text mode screens, while the next six screens are graphics mode screens. By default, the login process is started on the first 6 text mode screens, so we may start working by providing out username and password. The default graphical session starts on the seventh screen.

The Super User : Every Linux system has a super user, traditionally called root, who has all the privileges and can do anything and everything in the system. However, logging in and working as the super user is extremely risky, because in that case you have the potential to accidently cause serious damage to the system. For example, you may permanently delete some important file or directory by mistake, and the whole system may become unusable.