OPERATING SYSTEM: An operating system (OS) is the program that, after being initially loaded into the computer by a boot program, manages all the other programs in a computer. The other programs are called applications or application programs.
OPERATING SYSTEM ABSTRACTION
Abstraction is the concept of hiding irrelevant details. In other words, it makes complex systems simple by hiding the unnecessary detail from the user. Eg. For example, take a look at your mouse.
Is it wireless?
What kind of sensors does it have?
How many buttons?
Is it ergonomic?
How big is it?
The answers to all of these questions can precisely describe your mouse, but regardless of what the answers are, it’s still a mouse, because it’s a pointing device with buttons. That’s all it takes to be a mouse. “Silver Logitech MX518” is a concrete, specific item, and “mouse” is an abstraction of that. Software that hides lower level details and provides a set of high-level functions.
Abstraction is a technique for managing complexity by separating interface or interaction details away from lower-level implementation details.
OPERATIONS OF ABSTRACTION
- Mapping of files to storage
- Managing address space for each processor
- implements abstraction using available hardware supports like Paging, Segmentation etc
- Managing unit of resource allocation and one thread of execution.
The set of rules in a computer’s operating system for allocating the resources of the computer such as its peripheral devices or memory, to more than one program or user.
OPERATIONS OF ARBITRATION
- Allocation of memory or CPU time
- Arbitrate access to a shared device
MOBILE OPERATING SYSTEMS
Examples of mobile device operating systems include
- Apple iOS
- Google Android
- BlackBerry OS
- Palm OS (Garnet OS)
- Open WebOS
- Windows OS.
NB: Some, such as Microsoft’s Windows 10, 8.1 or 8, function as both a traditional desktop OS and a mobile operating system.
iOS was introduced in 29th June 2007 when the first iPhone was developed. Since then iOS has undergone many upgrades and currently, the latest one is the iOS 12.2.
User-friendly and is one of the mobile best-operating systems in the world. Makes use of iStore which is an application that allows the user to download authentic contents that run on iOS.
Very secure. High performance along with the appearance.
Apple has still not allowed any other manufacturer to lay hands on its operating system. Hard to share files among other phones running on other operating systems.
used on iPhones, IPads, and iPods.
September 20th, 2008 was the date when Google released the first Android OS by the name of ‘Astro’. After sometime next upgraded versions ‘Bender’ and ‘Cupcake’ were also released. Google then adopted the trend of naming Android versions after any dessert or a sweet in alphabetical order.
The other releases are Donut, Éclair, Froyo, Gingerbread, Honeycomb, Ice Cream Sandwich, Jelly Bean, Marshmallow and Nougat (Android 7.0) is so far the latest Android version from Google. Since the platform is not closed like iOS, there are too many great Android apps built by developers.
User-friendly and is one of the most popular mobile operating system in the world. Makes use of Google Play Store which is an application that allows the user to download applications that run on Android.
High performance along with the appearance.
it is less secure than the iOS and is prone to virus attack
used on many smartphones like Infinix X559,Samsung Galaxy S3, HTC ONE etc.
PC OPERATING SYSTEMS
Examples of PC operating systems include
- Microsoft Windows
- Mac OS X, Time Machine
- Ubuntu, Simplified Linux Setup
- Unix, The Shell Terminal
- BeOS, 64-Bit Journaling File System
- IRIX, SGI Dogfight
- NeXTSTEP, Right-Click Context Menu
- MS-DOS, BASIC
- iOS, Multi-Touch
Microsoft created the Windows operating system in the mid-1980s. Over the years, there have been many different versions of Windows, but the most recent ones are Windows 10 (released in 2015), Windows 8 (2012), Windows 7 (2009), and Windows Vista (2007). Windows comes pre-loaded on most new PCs, which helps to make it the most popular operating system in the world.
Mac OS is a line of operating systems created by Apple. It comes preloaded on all new Macintosh computers or Macs. All of the recent versions are known as OS X (pronounced OS Ten), and the specific versions include El Capitan (released in 2015), Yosemite (2014), Mavericks (2013), Mountain Lion (2012), and Lion (2011).
According to StatCounter Global Stats, Mac OS X users account for less than 10% of global operating systems—much lower than the percentage of Windows users (more than 80%). One reason for this is that Apple computers tend to be more expensive. However, many people do prefer the look and feel of Mac OS X over Windows.