System and Application Software

• Software consists of instructions, data, or programs.
• It operates computers and executes specific tasks.
• Software is a generic term for applications, scripts, and programs that run on devices.
• Computers cannot function without software.
• Software enables users to instruct a computer system, providing functions with business value.

System Software

• There are two major types of software: system software and application software.
• System software includes the operating system and utility programs.
• It controls the computer system allowing the use of the computer.

Application Software

• Application software programs allow the user to perform specific tasks on a computer.
• These tasks include word processing, playing games, browsing the web, and listening to music.

System Software Function

• System software directly operates the computer hardware.
• It provides basic functionality needed by users and other software.
• System software components are operating systems, device drivers and utilities.

Operating Systems

• Operating systems (OS) are software collections that manage resources.
• They also provide common services for other software.
• Common OS tasks are:
• Interfacing with Users (typically via a GUI).
• Booting the Computer, determining hardware connected to the computer.
• Configuring Devices, where device drivers are often needed and can be reinstalled, and Plug and Play devices are recognized automatically.
• Managing Network Connections for wired and wireless connections.
• Managing and Monitoring Resources, making resources available to devices and programs, monitoring for problems and attempting to correct those that arise.
• Scheduling jobs, including jobs to be printed, and files to be retrieved from hard drive.
• File management to keep track of stored files on a computer.
• The files can then be retrieved when needed, and files are usually viewed in a hierarchical format.
• Security is maintained using passwords and biometric characteristics.
• Memory Management optimizes the use of main memory (RAM), also it implements Virtual Memory.
• Virtual Memory technique uses hard drive space as additional RAM.

Operating Systems - Multitasking

• Multitasking is the ability of an operating system to have more than one program (task) open at one time.
• The CPU rotates between tasks.
• Switching is done quickly.
• It appears as though all programs are executing at the same time.

Operating Systems - Multithreading

• Multithreading is the ability to rotate between multiple threads.
• It means processing is completed faster and more efficiently.
• A thread is a sequence of instructions within a program and is independent of other threads.
• Multiprocessing uses multiple processors or multiple cores in one computer system to perform work more efficiently.
• Parallel processing is similar to multiprocessing.

Operating Systems - Interface

• Command Line Interface requires users to input commands using the keyboard.
• Graphical User Interface is graphics based and used by most operating systems.

Types of Operating Systems

• Personal (Desktop) Operating Systems are designed to be installed on a single computer.
• Server (Network) Operating Systems are designed to be installed on a network server.
• Client computers still use a personal operating system.
• Server operating system controls access to network resources.
• Mobile and embedded operating systems are also common.

Personal and Server Operating Systems commonly used by individuals

• Ms-Dos
• Windows is the most widely used
• Mac OS is powerful and easy to use
• UNIX is network designed originally for the web
• LINUX is non proprietary and is free from the Web

Operating Systems for Personal Computers and Servers

• Disk Operating System (DOS) which traditionally uses a command-line interface.
• DOS was the dominant operating system in the 1980s and early 1990s.

Windows

• Windows is the personal operating system developed by Microsoft Corporation.
• Windows 1.0 was released in 1985.
• It is designed for personal computers.
• Versions include Windows 95, Windows 98, Windows ME, Windows XP, Windows Vista, Windows 7 (2009), Windows 8, and Windows 11.
• Windows Server is designed for server use.

UNIX and LINUX

• UNIX is an operating system developed in the late 1960s for midrange servers.
• It is a multiuser, multitasking operating system.
• UNIX is more expensive and requires high level of technical knowledge.
• LINUX was developed by Linus Torvalds in 1991.
• It originally used a command line interface although recent versions use a GUI.

Mac OS

• Mac OS is the operating system made by Apple Corporation.
• It is based on the UNIX operating system
• The Mac OS X Family is the Mac OS X Server.

Mobile Operating System - Android

• Android is a Linux-based operating system created with current mobile device capabilities in mind.
• Focus is on mobile payment transactions and Internet phone calls.
• Android devices support multitasking and multiple cores.

Mobile Operating System - iOS

• iOS is designed for Apple Mobile phones and mobile devices.
• It supports multitasking.
• Included is the Safari Web browser, the Siri intelligent assistant, and Facetime video calling.
• Features AirDrop to send items to others and apps for email, messaging, music, and search.

Utilities

• Utilities are software that perform a specific task.
• Primarily related to managing or maintaining the computer system.
• Essential utilities are troubleshooting programs, antivirus, backup program makes copies of files to restore originals.
• File compression programs reduces the size of the file requiring less storage space.

Windows Utilities

• File History creates a backup for the hard drive.
• Disk Cleanup assists in getting rid of unnecessary files.
• Disk Defragmenter rearranges files and unused disk space to optimize performance.

File History

• File History is a utility program included with Windows 8.
• It makes a copy of all files in the libraries, contacts, favorites and the desktop.
• This helps prevent the effect of disk failure.

Disk Cleanup

• Disk Cleanup identifies and eliminates nonessential files
• It frees up valuable space and improves system performance

Disk Defragmenter

• Files are organized in tracks and sectors.
• This identifies and eliminates unnecessary fragments.
• It rearranges files and unused disk space to optimize operations.

Device Drivers

• Device Drivers allow communication between a device and the computer.
• They are loaded into memory each time a computer is started.
• When a new device is added, new device drivers must be installed as well.
• This is done by Adding a Device Wizard which is step-by-step.
• Windows already has many drivers within the system software.
• There is a possibility to update the device drivers in case they are not running properly.