Presentation Transcript
COSC1078 Introduction toInformation Technology: COSC1078 Introduction to Information Technology Bao Quoc Vo
vqbao@cs.rmit.edu.au
http://www.cs.rmit.edu.au/~vqbao
10.11.14
In today lecture …: In today lecture … Operating Systems
Our focus
Desktop Operating systems
Microsoft Windows, Linux, MacOS
Desktop applications
Operating Systems: Operating Systems An operating system (OS) is a set of computer programs that manage the hardware and software resources of a computer.
At the foundation of all system software, an operating system performs basic tasks such as controlling and allocating memory, prioritizing system requests, controlling input and output devices, facilitating networking, and managing file systems.
Most operating systems have a command line interpreter as a basic user interface, but they may also provide a graphical user interface (GUI) for ease of operation.
OS interfaces: OS interfaces
Computer System Structure: Computer System Structure HARDWARE
Closer look to computer system: Closer look to computer system
Example (Simple Error Box): Example (Simple Error Box) Device Drivers APIs Application
Software Kernel Call API Draw an error box with text 'Error' and 'OK' button Draw a gray and a blue box
Draw a button
Render 'OK' and 'Error' and display them Necessary
Calculations Call the Kernel Memory
locations for
X and Y Low level
basic logic
Operating Systems:Basic responsibilities and services: Operating Systems: Basic responsibilities and services Process management:
Processes are running instances of programs on a computer.
Modern operating systems enable concurrent execution of many processes at once via multitasking even with one CPU.
Memory management:
Modern computer's memory is arranged in a hierarchical manner: registers, CPU cache, random access memory and disk storage.
An operating system coordinates the use of various types of memory by tracking which one is available, which is to be allocated or deallocated and how to move data between them.
Basic responsibilities and services: Basic responsibilities and services Disk and file systems:
Files containing data and programs on a computer are organised into file systems and stored on storage devices, such as disks.
Networking:
Most current operating systems are capable of using some networking protocols to allow a computer to be connected to a network and enable resources, e.g. files, printer, scanners, etc. to be shared between different computers
Basic responsibilities and services: Basic responsibilities and services Security
Graphical user interface
Device drivers
OS Categories: OS Categories Operating Systems are divided into three Categories:
Desktop Operating Systems
Server Operating Systems
Specialist Operating Systems
Desktop Operating Systems: Desktop Operating Systems Fairly reliable Kernel design
Plug and Play
Highly featured API
User friendly Interface
Popular Desktop Operating Systems
Microsoft Windows
Linux
Apple MacOS X
Desktop OS Popularity: Desktop OS Popularity Microsoft Windows Linux and Others More than 85%
Linux: Linux
About Linux: About Linux Open Source
Developed for the first time in 1991 by a Finnish student
Written in C
Red Hat, SUSE, Mandrake (Mandriva)
Red Hat 7.1 has more than 30 million lines of source code
GNOME and KDE
LAMP (Linux, Apache, MySQL, Perl/PHP/Python)
Routers and Firewalls
Picture from Wikipedia
About Windows: About Windows Add-on to MS-DOS in 1985
Multi-tasking
The Most Popular OS
Security issues
Windows Vista 2007 Picture from Wikipedia
About MacOS: About MacOS Macintosh Operating System
Introduced by Apple in 1984
Graphical user interface (unlike MS-DOS)
Unix Based
MacOS X x86 (Jan 2006)
Graphical features Picture from Wikipedia
Operating Systems (continued): Operating Systems (continued) Server Operating Systems
Highly reliable
Usually Microsoft Windows Server or Unix
Specialist Operating Systems
Mainframe operating systems, e.g. IBM’s z/OS
Real-time scheduling
embedded operating systems such as VxWorks, eCos, Palm OS, etc.
Small size
Example of application software: Graphics & Design: Example of application software: Graphics andamp; Design