Linux Operating System Architecture X Window Word Processing, Web Browsing, File Access, etc. Windows Management Memory Management File Systems Device Control Network Control Linux Operating System Architecture Process Management Kernel Operating System Platform Dependent Code RAM and Swap Block Data Drivers Character Data Drivers Network Interface Drivers CPU RAM Disk Drives Serial and Parallel Ports Network Interfaces Computer Hardware Computer Hardware

Word Processing, Web Browsing, File Access, etc. X Window Word Processing, Web Browsing, File Access, etc. Windows Management

X Windows & Windows Manager The graphical user interface (GUI) is the point and click environment with which most Windows users are familiar. In Linux, GUI can be many different interfaces (KDE, GNOME and more). The X Window GUI is started early in order to control the input device (keyboard, mouse, etc…) and the output (computer monitor). The Windows Manager allows you to create, move, minimize and transfer between windows on the desktop.

Platform Dependent Code RAM and Swap Block Data Drivers Memory Management File Systems Device Control Network Control Process Management Kernel Operating System Platform Dependent Code RAM and Swap Block Data Drivers Character Data Drivers Network Interface Drivers CPU RAM Disk Drives Serial and Parallel Ports Network Interfaces Computer Hardware Computer Hardware

LINUX KERNEL The Kernel is the “core” of a Linux operating system. Without it you have a box with useless hardware that generates heat. The purpose of the Linux Kernel is to manage all hardware, programs and control all system communications. The Kernel refers to a running program as a process. The Kernel, starts/stops the process, manages its communications and coordinates its access of hardware resources.

Platform Dependent Code RAM and Swap Block Data Drivers Memory Management File Systems Device Control Network Control Process Management Kernel Operating System Platform Dependent Code RAM and Swap Block Data Drivers Character Data Drivers Network Interface Drivers RAM Disk Drives Computer Hardware Computer Hardware

LINUX KERNEL - Memory One primary function of the Operating System is memory management. That includes not only physical memory (RAM) but also the virtual memory swap area. When a process is started, its code is loaded into RAM as pages by memory management to allow the program to execute (run). As the RAM area fills with additional processes, memory management moves the code for less active processes to the hard drive swap area.

Platform Dependent Code Virtual Memory “Swap” Block Data Drivers Memory Management File Systems Device Control Network Control Process Management Kernel Operating System Platform Dependent Code Virtual Memory “Swap” Block Data Drivers Character Data Drivers Network Interface Drivers Disk Drives Network Interfaces Computer Hardware Computer Hardware

LINUX KERNEL – File System The file system manager supports over a dozen different types of file systems by providing read and write functions between the various disk drives and active applications. The Linux kernel interfaces with the various file systems on the computer using a Virtual File System scheme to present the different systems as one file system.

Platform Dependent Code Virtual Memory “Swap” Block Data Drivers Memory Management File Systems Device Control Network Control Process Management Kernel Operating System Platform Dependent Code Virtual Memory “Swap” Block Data Drivers Character Data Drivers Network Interface Drivers Disk Drives Serial and Parallel Ports Network Interfaces Computer Hardware Computer Hardware

LINUX KERNEL – Hardware Hardware management is the process of controlling communications between the Operating System and the hardware devise. This communication is facilitated with the use of an additional bit of software known as a device driver that is specifically designed for the particular hardware device. The device driver is installed within the Linux kernel to directly interface with the hardware it was designed to support.

LINUX KERNEL – Hardware The Operating System communicates with all device drivers over the internal bus and depends on the device driver to do the conversion needed to communicate with its particular hardware device. Device drivers transmit and receive data to and from the hardware device in these formats: Character - data passed one character at a time. Block - data passed as blocks of multiple characters. Network – data passed as multiple character packets with control characters.

Software Windows Cost Linux Windows XP $104 Ububtu $0 Windows Office MS Word MS Excel MS Power Point MS Access MS Publisher MS Outlook $330 Open Office .org Writer Calc Impress Base Draw Thunderbird (separate) Photo Shop $190 GIMP Grand Total $624