Features unique to recent versions of the ios operating system include ____.

operating system (OS), program that manages a computer’s resources, especially the allocation of those resources among other programs. Typical resources include the central processing unit (CPU), computer memory, file storage, input/output (I/O) devices, and network connections. Management tasks include scheduling resource use to avoid conflicts and interference between programs. Unlike most programs, which complete a task and terminate, an operating system runs indefinitely and terminates only when the computer is turned off.

Modern multiprocessing operating systems allow many processes to be active, where each process is a “thread” of computation being used to execute a program. One form of multiprocessing is called time-sharing, which lets many users share computer access by rapidly switching between them. Time-sharing must guard against interference between users’ programs, and most systems use virtual memory, in which the memory, or “address space,” used by a program may reside in secondary memory (such as on a magnetic hard disk drive) when not in immediate use, to be swapped back to occupy the faster main computer memory on demand. This virtual memory both increases the address space available to a program and helps to prevent programs from interfering with each other, but it requires careful control by the operating system and a set of allocation tables to keep track of memory use. Perhaps the most delicate and critical task for a modern operating system is allocation of the CPU; each process is allowed to use the CPU for a limited time, which may be a fraction of a second, and then must give up control and become suspended until its next turn. Switching between processes must itself use the CPU while protecting all data of the processes.

Computers and Operating Systems

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The first digital computers had no operating systems. They ran one program at a time, which had command of all system resources, and a human operator would provide any special resources needed. The first operating systems were developed in the mid-1950s. These were small “supervisor programs” that provided basic I/O operations (such as controlling punch card readers and printers) and kept accounts of CPU usage for billing. Supervisor programs also provided multiprogramming capabilities to enable several programs to run at once. This was particularly important so that these early multimillion-dollar machines would not be idle during slow I/O operations.

Computers acquired more powerful operating systems in the 1960s with the emergence of time-sharing, which required a system to manage multiple users sharing CPU time and terminals. Two early time-sharing systems were CTSS (Compatible Time Sharing System), developed at the Massachusetts Institute of Technology, and the Dartmouth College Basic System, developed at Dartmouth College. Other multiprogrammed systems included Atlas, at the University of Manchester, England, and IBM’s OS/360, probably the most complex software package of the 1960s. After 1972 the Multics system for General Electric Co.’s GE 645 computer (and later for Honeywell Inc.’s computers) became the most sophisticated system, with most of the multiprogramming and time-sharing capabilities that later became standard.

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The minicomputers of the 1970s had limited memory and required smaller operating systems. The most important operating system of that period was UNIX, developed by AT&T for large minicomputers as a simpler alternative to Multics. It became widely used in the 1980s, in part because it was free to universities and in part because it was designed with a set of tools that were powerful in the hands of skilled programmers. More recently, Linux, an open-source version of UNIX developed in part by a group led by Finnish computer science student Linus Torvalds and in part by a group led by American computer programmer Richard Stallman, has become popular on personal computers as well as on larger computers.

In addition to such general-purpose systems, special-purpose operating systems run on small computers that control assembly lines, aircraft, and even home appliances. They are real-time systems, designed to provide rapid response to sensors and to use their inputs to control machinery. Operating systems have also been developed for mobile devices such as smartphones and tablets. Apple Inc.’s iOS, which runs on iPhones and iPads, and Google Inc.’s Android are two prominent mobile operating systems.

From the standpoint of a user or an application program, an operating system provides services. Some of these are simple user commands like “dir”—show the files on a disk—while others are low-level “system calls” that a graphics program might use to display an image. In either case the operating system provides appropriate access to its objects, the tables of disk locations in one case and the routines to transfer data to the screen in the other. Some of its routines, those that manage the CPU and memory, are generally accessible only to other portions of the operating system.

Contemporary operating systems for personal computers commonly provide a graphical user interface (GUI). The GUI may be an intrinsic part of the system, as in the older versions of Apple’s Mac OS and Microsoft Corporation’s Windows OS; in others it is a set of programs that depend on an underlying system, as in the X Window system for UNIX and Apple’s Mac OS X.

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Operating systems also provide network services and file-sharing capabilities—even the ability to share resources between systems of different types, such as Windows and UNIX. Such sharing has become feasible through the introduction of network protocols (communication rules) such as the Internet’s TCP/IP.

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You’ve probably been involved in a “PC versus Mac” argument at some point in your life. Everyone seems to have very strong opinions on the subject, but what it really comes down to is personal preference in operating systems.

Most people know that they like one or another but may not be able to pinpoint what they really prefer about them. They may say they like a particular command prompt, or they enjoy some pre-installed software, the look and feel of the hardware, the applications or systems they can download, or even the pre-installed web browser. But the reality is that the features of an OS aren’t immediately clear to most users. A resource to help users understand the different processing and interaction elements of their favorite OS helps it become easier to work with.

Students (particularly online students), freelancers, contractors, and anyone who owns a phone, computer, or tablet should learn about different OSs so they can pick a computer and OS that meet their needs. If you’re planning to study IT in school and pursue an IT career, you’ll want a strong knowledge of OSs to make sure you’re prepared for all the skills you’ll need to be successful in your field.

Operating systems contain and manage all the programs and applications that a computer or mobile device is able to run, which means managing the device’s software and hardware functions. The functions of an OS include:

• Booting: Booting is the process of turning on the computer and powering up the system.
• Memory management: This feature controls and coordinates the computer applications while allocating space for programs.
• Loading and execution: Your OS will load, or start up, a program and then execute the program so that it opens and runs.
• Data security: A good OS includes features that keep your data safe and computer programs secure. Security features are set up to keep unwanted cyberattackers at bay.
• Disk management: This manages all the drives installed in a computer, including hard drives, optical disk drives, and flash drives. Disk management can also be used to divide disks, format drives, and more.
• Process management: Your OS is designed to allocate resources to different computer processes, enable the processes to share information, protect them, and synchronize them.
• Device controlling: Your OS will allow you to open or block access to devices like removable devices, CD/DVDs, data transfer devices, USBs, and more.
• Printing controlling: As an extension of device controlling, your OS takes control of the printers that are connected to the computer, and the materials that need to be printed.
• User interface: Also referred to as a UI, this is the part of the OS that allows a user to enter and receive information. This can be done with typed commands, code, and other formats.

There are five main types of operating systems. These five OS types are likely what run your phone, computer, or other mobile devices like a tablet. Whether you’re just a normal computer and phone user or someone hoping to get involved in an IT career, knowledge of applications and systems types will help you maintain security and user access, perform routine operations, and much more.

The Windows OS has been around since the 1980s and has had several versions and updates (including Windows 95, Windows Vista, Windows 7/8/10, etc.) Microsoft Windows is one of the popular operating system types and is preloaded on most new PC hardware. With each new Windows update or release, Microsoft continues to work on improving their users’ experience, hardware, and software, making Windows more accessible and easier to use.

Microsoft Windows contains a control panel, a desktop and desktop assistant, disk cleanup, event viewer, and more. Many users prefer Microsoft Windows because they say it’s compatible with many other kinds of software. Many kinds of computer programs run best on Microsoft Windows because they’re developed by Microsoft.

Head-to-head in the competition with Microsoft Windows is Apple’s macOS. macOS and Windows are both examples of proprietary operating systems, meaning that the company conceptualized, designed, developed, and now sells their own OS. They’re designed and sold by the companies and aren’t meant to be tampered with or tweaked by users. Apple and Macintosh computers run on the proprietary macOS and OS X system, the first of which launched 20 years ago. There are also previous versions or updates which include:

Kodiak (OS X 10 Beta)

Lion (OS X 10.7)

Mountain Lion (OS X 10.8)

Mavericks (OS X 10.9)

Yosemite (OS X 10.10)

El Capitan (OS X 10.11)

Sierra (macOS 10.12)

High Sierra (macOS 10.13)

Mojave (macOS 10.14)

Catalina (macOS 10.15)

Big Sur (macOS 11)

The macOS and Apple/Mac products are also known and beloved by their users for ease of use and continually improving user experience. Fast processing speeds, a simple desktop interface, and a wide variety of helpful resources make users excited about macOS. Many users relish the instant connection with their computers and mobile phone hardware, and enjoy the lack of bugs and hackers that Apple systems are known for.

The OS that companies including Google use to run its Android mobile smartphones and tablets is based on Linux distribution and other open source software. Android OS is the primary OS for Google mobile devices like smartphones and tablets. Android has gained increasing popularity since its release as an alternative to Apple’s iOS for smartphone users and is continuing to increase in popularity with new updates and exciting features.

Apple's iOS is another mobile operating system used exclusively for iPhones, some of the most popular mobile devices on the market. iOS integrations have regular updates, new expansions to software, and continually are offering new features for users even if they have older devices. 

Many users appreciate the unique user interface with touch gestures, and the ease of use that iOS offers. This operating system also allows other Apple devices to connect, giving users easy connections to other devices or people.

Linux is different from Windows and Apple in that it’s not a proprietary software, but rather a family of open source systems. In other words, anyone can modify and distribute it. Linux may be the least known on this list, but it’s free and available in many different open source versions. Linux is popular because of its ease of customization and offers a variety of options to those who understand how to use it. If you know how to customize and work with operating systems, Linux is an ideal choice. And if this kind of coding and back-end work is interesting to you, it may be a good idea to purchase a Linux system and get started on manipulating it.

Some examples of operating systems include Apple macOS, Microsoft Windows, Google’s Android OS, Linux Operating System, and Apple iOS. Apple macOS is found on Apple personal computers such as the Apple Macbook, Apple Macbook Pro and Apple Macbook Air. Microsoft Windows is found on a variety of personal computer platforms from brands such as HP, Dell, and Microsoft itself. Linux is an open source OS that can be modified by users, unlike those from Apple or Microsoft. Though it started out being used for personal computers, usage has since expanded to phones and other smart devices, servers, gaming, and more.

Android is a Unix-like mobile operating system that you’ll find on your mobile phone or tablet, depending on the device brand. Similarly, Apple iOS is found on Apple mobile devices such as an iPhone (though it previously ran on Apple iOS, iPad now has its own OS called iPad OS).

So why are there different types of operating systems for mobile tech and computers? There are several reasons a single system doesn’t work perfectly for both. Computer and mobile OSs are different because they’re developed for different uses.

Computer systems have to store lots of complex data, have a different user interface, and need to be prepared for printing, removable disks, and more. They feature a desktop and a control panel for users to manage all of their information. Computer operating systems are also older, and therefore more familiar to the IT industry; they’ve been around much longer than phones that utilize operating systems.

Mobile phones don't feature a desktop that's the same as a computer desktop. Their user interface is much more about simple moves—things you can do with your fingers or voice—so it’s designed to offer a simpler interface. There are many resources to help users learn more about operating mobile phone systems, as they're very different from computer systems.

Touch screen user interfaces, smartphones, and mobile devices are everywhere and part of life, and need operating systems. If you’re considering a career in IT, you probably know that the technology is continuing to grow and develop, and there will be plenty of opportunities for the future.

For the most part, the IT industry largely focuses on the top five OSs, including Apple macOS, Microsoft Windows, Google’s Android OS, Linux Operating System, and Apple iOS. But that’s just the tip of the operating system iceberg. There are numerous free OS options in addition to Linux including Chrome OS, Syllable, and ReactOS, which was initially launched as a Windows95 clone. 

But that’s just in the world of personal computers, mobile devices, and tablets. When you examine server OSs, the number jumps considerably. All told, there are over 63 base proprietary OSs with various versions or updates, in addition to another 26 non-proprietary OSs.

As tech continues to advance, and as younger generations like millennials grow up with technology and move to the workforce, the need for technology in business settings will only grow. Younger generations are fueling the features and applications that operating systems provide for personal and business use. If you’re considering a degree in IT, now is the time to start. A future career in computers or IT will provide you with plenty of job opportunities, industries, and endless possibilities.