Mac OS X (pronounced /ˈmæk ˌoʊ ˌɛs ˈtɛn/ mak oh es ten)[6] is a series of Unix-based operating systems and graphical user interfaces developed, marketed, and sold by Apple Inc. Since 2002, Mac OS X has been included with all new Macintosh computer systems. It is the successor to Mac OS 9, the final release of the "classic" Mac OS, which had been Apple's primary operating system since 1984.
Mac OS X, whose X is the Roman numeral for 10 and is a prominent part of its brand identity, is a Unix-based graphical operating system,[7] built on technologies developed at NeXT between the second half of the 1980s and Apple's purchase of the company in late 1996. From its sixth release Mac OS X v10.5 "Leopard" and onwards, every release of Mac OS X gained UNIX 03 certification while running on Intel processors.[3][4]
The first version released was Mac OS X Server 1.0 in 1999, and a desktop-oriented version, Mac OS X v10.0 "Cheetah" followed on March 24, 2001. Releases of Mac OS X are named after big cats: for example, Mac OS X v10.6 is usually referred to by Apple and users as "Snow Leopard". The server edition, Mac OS X Server, is architecturally identical to its desktop counterpart, and includes tools to facilitate management of workgroups of Mac OS X machines, and to provide access to network services. These tools include a mail transfer agent, a Samba server, an LDAP server, a domain name server, and others. It is pre-loaded on Apple's Xserve server hardware, but can be run on almost all of Apple's current selling computer models.[8]
Apple also produces specialized versions of Mac OS X for use on four of its consumer devices: the iOS for the iPhone, iPod Touch,[9] and iPad, as well as an unnamed version for the Apple TV
The Macintosh (pronounced /ˈmæk.ɪn.tɒʃ/ MAK-in-tosh),[1] or Mac, is a series of several lines of personal computers designed, developed, and marketed by Apple Inc. The first Macintosh was introduced on January 24, 1984; it was the first commercially successful personal computer to feature a mouse and a graphical user interface rather than a command-line interface.[2] The company continued to have success through the second half of the 1980s, only to see it dissipate in the 1990s as the personal computer market shifted towards IBM PC compatible machines running MS-DOS and Microsoft Windows.[3]
Apple consolidated its multiple consumer-level desktop models years later into the 1998 iMac all-in-one. This proved to be a sales success and saw the Macintosh brand revitalized, albeit not to the market share level it once had. Current Mac systems are mainly targeted at the home, education, and creative professional markets. They are: the aforementioned (though upgraded and modified in various ways) iMac and the entry-level Mac mini desktop models, the workstation-level Mac Pro tower, the MacBook, MacBook Air and MacBook Pro laptops, and the Xserve server.
Production of the Mac is based on a vertical integration model in that Apple facilitates all aspects of its hardware and creates its own operating system that is pre-installed on all Mac computers. This is in contrast to most IBM PC compatibles, where multiple sellers create hardware intended to run another company's operating software. Apple exclusively produces Mac hardware, choosing internal systems, designs, and prices. Apple does use third party components, however. Current Mac CPUs use Intel's x86 architecture; the earliest models (1984–1994) used Motorola's 68k and models from 1994–2006 used the AIM alliance's PowerPC. Apple also develops the operating system for the Mac, currently Mac OS X version 10.6 "Snow Leopard". The modern Mac, like other personal computers, is capable of running alternative operating systems such as Linux, FreeBSD, and, in the case of Intel-based Macs, Microsoft Windows. However, Apple does not license Mac OS X for use on non-Apple computers.
Thursday, August 26, 2010
The Relationship between an Application program, the operating system and hardware
Computer Hardware consists of the physical components that make up a computer. Some examples are and Microprocessor, a Hard Drive, or a Motherboard.
Computer Software consists of applications or programs that the user runs on a computer, such as a word processor or a video game.
An Operating System is a specific piece of software that allows other software to manipulate computer hardware to achieve a desired effect. Some Operating Systems are Microsoft Windows, Unix/Linux, or Apple OS
Basically the three interact as follows:
Hardware <-> Operating System <-> Software
(<-> specifies an interaction between two components.)
In addition computer hardware deal with different devices that interact into the computer software then it show the capacity and data of the applications while the operating system it is the combination of performance which spreadout to access each other components.
Computer Software consists of applications or programs that the user runs on a computer, such as a word processor or a video game.
An Operating System is a specific piece of software that allows other software to manipulate computer hardware to achieve a desired effect. Some Operating Systems are Microsoft Windows, Unix/Linux, or Apple OS
Basically the three interact as follows:
Hardware <-> Operating System <-> Software
(<-> specifies an interaction between two components.)
In addition computer hardware deal with different devices that interact into the computer software then it show the capacity and data of the applications while the operating system it is the combination of performance which spreadout to access each other components.
A Description of the Boot Process
A Description of the Boot Process
• In order for a computer to successfully boot, its BIOS, operating system and hardware components must all be working properly; failure of any one of these three elements will likely result in a failed boot sequence.
• When the computer's power is first turned on, the CPU initializes itself, which is triggered by a series of clock ticks generated by the system clock. Part of the CPU's initialization is to look to the system's ROM BIOS for its first instruction in the startup program. The ROM BIOS stores the first instruction, which is the instruction to run the power-on self test (POST), in a predetermined memory address. POST begins by checking the BIOS chip and then tests CMOS RAM. If the POST does not detect a battery failure, it then continues to initialize the CPU, checking the inventoried hardware devices (such as the video card), secondary storage devices, such as hard drives and floppy drives, ports and other hardware devices, such as the keyboard and mouse, to ensure they are functioning properly.
• Once the POST has determined that all components are functioning properly and the CPU has successfully initialized, the BIOS looks for an OS to load.
• The BIOS typically looks to the CMOS chip to tell it where to find the OS, and in most PCs, the OS loads from the C drive on the hard drive even though the BIOS has the capability to load the OS from a floppy disk, CD or ZIP drive. The order of drives that the CMOS looks to in order to locate the OS is called the boot sequence, which can be changed by altering the CMOS setup. Looking to the appropriate boot drive, the BIOS will first encounter the boot record, which tells it where to find the beginning of the OS and the subsequent program file that will initialize the OS.
• Once the OS initializes, the BIOS copies its files into memory and the OS basically takes over control of the boot process. Now in control, the OS performs another inventory of the system's memory and memory availability (which the BIOS already checked) and loads the device drivers that it needs to control the peripheral devices, such as a printer, scanner, optical drive, mouse and keyboard. This is the final stage in the boot process, after which the user can access the system’s applications to perform tasks.
A Description of the Boot Process
• In order for a computer to successfully boot, its BIOS, operating system and hardware components must all be working properly; failure of any one of these three elements will likely result in a failed boot sequence.
• When the computer's power is first turned on, the CPU initializes itself, which is triggered by a series of clock ticks generated by the system clock. Part of the CPU's initialization is to look to the system's ROM BIOS for its first instruction in the startup program. The ROM BIOS stores the first instruction, which is the instruction to run the power-on self test (POST), in a predetermined memory address. POST begins by checking the BIOS chip and then tests CMOS RAM. If the POST does not detect a battery failure, it then continues to initialize the CPU, checking the inventoried hardware devices (such as the video card), secondary storage devices, such as hard drives and floppy drives, ports and other hardware devices, such as the keyboard and mouse, to ensure they are functioning properly.
• Once the POST has determined that all components are functioning properly and the CPU has successfully initialized, the BIOS looks for an OS to load.
• The BIOS typically looks to the CMOS chip to tell it where to find the OS, and in most PCs, the OS loads from the C drive on the hard drive even though the BIOS has the capability to load the OS from a floppy disk, CD or ZIP drive. The order of drives that the CMOS looks to in order to locate the OS is called the boot sequence, which can be changed by altering the CMOS setup. Looking to the appropriate boot drive, the BIOS will first encounter the boot record, which tells it where to find the beginning of the OS and the subsequent program file that will initialize the OS.
• Once the OS initializes, the BIOS copies its files into memory and the OS basically takes over control of the boot process. Now in control, the OS performs another inventory of the system's memory and memory availability (which the BIOS already checked) and loads the device drivers that it needs to control the peripheral devices, such as a printer, scanner, optical drive, mouse and keyboard. This is the final stage in the boot process, after which the user can access the system’s applications to perform tasks.
A Description of the Boot Process
What does a driver do?
A driver is a specially written program which understands the operation of the device it interfaces to, such as a printer, video card, sound card or CD ROM drive. It translates commands from the operating system or user into commands understood by the the component computer part it interfaces with. It also translates responses from the component computer part back to responses that can be understood by the operating system, application program, or user. The below diagram gives a graphical depiction of the interfaces between the operating system and the computer component.
What is an Operating System
The operating system is the core software component of your computer. It performs many functions and is, in very basic terms, an interface between your computer and the outside world. In the section about hardware, a computer is described as consisting of several component parts including your monitor, keyboard, mouse, and other parts. The operating system provides an interface to these parts using what is referred to as "drivers". This is why sometimes when you install a new printer or other piece of hardware, your system will ask you to install more software called a driver.
The Environment Considerations in the Disposal of Computer Hardware and OH+S considerations in the use of computer equipment.
Environmental Considerations in the disposal of computer system.
There is large Carbon footprint in IT production industry but that can be reduced by re-use and re-deployment of redundant IT equipments known as Computer Recycling.
Most of the environmental concerns with computers lie with the monitor, specifically its catode ray tube (CRT). On average, each color monitor contains 4 to 5 pounds of lead, considered hazardous waste when disposed of.
There are other hazardous materials in computers, including mercury, cadmium (also known carcinogen), and hexavalen Chromium (cause high blood pressure, iron-poor blood, liver disease, and nerve and brain damage in animals). Over 314 million computers were thrown away at the end of 2007.
Computer Recycling problem is, after upgrading computer system, most organizations store their old computers, which serve as backup equipment in case newer computers break down. decision must be made at some point about disposal of this equipment as continuing to store old computers is often not a viable option, it eventually takes up a considerable amount of space. The least desirable option is to throw old computers into the bin. computer recycling comes into the fore in every possible scenario, not just the effect it has upon the environment, there is also the possibility of someone removing hard drives and recovering sensitive data.
This drives to the point that data on hard disks should be destroyed - before getting rid of the computer or hard disk in it. Computer recycling isn't always about the environment, but of company and national safety importance too.
From an environmental point of view, it is far better to recycle your computer at an official recycling centre than to dispose of it.
Reference : Article source: http://EzineArticles.com/?Computer-Recycling-For-Environmental-issues&id=1293414 , John Pettifer, 2009 EzineArticles.com - All Rights Reserved Worldwide.
B) OH+S considerations in the use of Computer Systems
Ergonomics is the term that refers to scitific discipline concerned with design according to human needs. It looks at what kind of work you do, what equipment you use and your entire job environment. The goal of ergonomics is to find best fit between you and your job conditions.
To setup an ergonomic computer workstation , make sure that teh computer is placed on a stable working surface with adequate room for proper arrangement. It's important to choose a comfortable chair for the user to sit in. Chair should be adjusted at a fixed height provided that its comfortable and has a good backrest that provides lumbar support.
A good workstation design will allow any computer user to work in a neutral, ideal typing posture that will minimize the risk of deveoping any injury.
A good workstation setup may include:
• Ergonomics keyboards and mouse
• Wrist rests
• Support braces/gloves
Other considerations are the following environmental conditions where computer will be used
• Lighting
• Ventilation
• Noise Take a break!
Make sure to practice the following to help avoid strain and injury
• Eye breaks every 15 minutes
• Rest breaks every 30 to 60 minutes.
• Exercise break every 1-2 hours.
There is large Carbon footprint in IT production industry but that can be reduced by re-use and re-deployment of redundant IT equipments known as Computer Recycling.
Most of the environmental concerns with computers lie with the monitor, specifically its catode ray tube (CRT). On average, each color monitor contains 4 to 5 pounds of lead, considered hazardous waste when disposed of.
There are other hazardous materials in computers, including mercury, cadmium (also known carcinogen), and hexavalen Chromium (cause high blood pressure, iron-poor blood, liver disease, and nerve and brain damage in animals). Over 314 million computers were thrown away at the end of 2007.
Computer Recycling problem is, after upgrading computer system, most organizations store their old computers, which serve as backup equipment in case newer computers break down. decision must be made at some point about disposal of this equipment as continuing to store old computers is often not a viable option, it eventually takes up a considerable amount of space. The least desirable option is to throw old computers into the bin. computer recycling comes into the fore in every possible scenario, not just the effect it has upon the environment, there is also the possibility of someone removing hard drives and recovering sensitive data.
This drives to the point that data on hard disks should be destroyed - before getting rid of the computer or hard disk in it. Computer recycling isn't always about the environment, but of company and national safety importance too.
From an environmental point of view, it is far better to recycle your computer at an official recycling centre than to dispose of it.
Reference : Article source: http://EzineArticles.com/?Computer-Recycling-For-Environmental-issues&id=1293414 , John Pettifer, 2009 EzineArticles.com - All Rights Reserved Worldwide.
B) OH+S considerations in the use of Computer Systems
Ergonomics is the term that refers to scitific discipline concerned with design according to human needs. It looks at what kind of work you do, what equipment you use and your entire job environment. The goal of ergonomics is to find best fit between you and your job conditions.
To setup an ergonomic computer workstation , make sure that teh computer is placed on a stable working surface with adequate room for proper arrangement. It's important to choose a comfortable chair for the user to sit in. Chair should be adjusted at a fixed height provided that its comfortable and has a good backrest that provides lumbar support.
A good workstation design will allow any computer user to work in a neutral, ideal typing posture that will minimize the risk of deveoping any injury.
A good workstation setup may include:
• Ergonomics keyboards and mouse
• Wrist rests
• Support braces/gloves
Other considerations are the following environmental conditions where computer will be used
• Lighting
• Ventilation
• Noise Take a break!
Make sure to practice the following to help avoid strain and injury
• Eye breaks every 15 minutes
• Rest breaks every 30 to 60 minutes.
• Exercise break every 1-2 hours.
Internal hardware components, cost, image and function
CPU
Power Supply
Card expansions (i.e. sound card, video card, etc.)
Also, there's bunches of fans (mainly the CPU fan, chassis fan, and graphics card fan)
Hard Drive[s]
CD/DVD/Floppy disk drives
Adapters, if you need them
a. Power Supply - The power supply comes with the case, but this component is mentioned separately since there are various types of power supplies. The one you should get depends on the requirements of your system. This will be discussed in more detail later
b. Motherboard - This is where the core components of your computer reside which are listed below. Also the support cards for video, sound, networking and more are mounted into this board.
i. Microprocessor - This is the brain of your computer. It performs commands and instructions and controls the operation of the computer.
ii. Memory - The RAM in your system is mounted on the motherboard. This is memory that must be powered on to retain its contents.
iii. Drive controllers - The drive controllers control the interface of your system to your hard drives. The controllers let your hard drives work by controlling their operation. On most systems, they are included on the motherboard, however you may add additional controllers for faster or other types of drives.
2) RAM- Random-access memory (RAM) is a form of computer data storage. Today, it takes the form of integrated circuits that allow stored data to be accessed in any order (i.e., at random). "Random" refers to the idea that any piece of data can be returned in a constant time, regardless of its physical location and whether or not it is related to the previous piece of data.
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