BY: MOLLY LEPINE AND STACEY RAAPIT 101

Operating Systems

What is an Operating System????

An Operating System (OS) is set of computer programs that runs or controls the computer hardware

Operating Systems also act as an interface with both application programs and users

Why do we need OS????

Operating Systems play a central role in the functioning of all computer systems

They help most digital devices operateEvery computer is controlled by an OS,

usually find software stored on a disk

What do OS do????

Control computer hardware

Manage memoryManage processorsControl input and

output devices

What do OS Do???? (cont.)

Store and manipulation filesProve a user interface

Most today provide networking featuresSome support larger computer systems

Specifications of OS

Designed to work with specific types of computers and processors

Application software works specifically with a particular operating system

Interactions

Provides a user interface that allows you to interact with the system

User Interface: What defines the users experience and causes some users to prefer Windows or MAC’s

Organization

OS provide structure for organizing data on the system

Data is stored in files which are put in folders and sub folders

Communication

Communicates with hundreds of external devices – which are peripheral devices- through device drivers

Device Driver Software that is installed for each device connected to

a PC that allows the OS to communicate with that device

OS Control

Controls processing and memory useHow?

Retrieve instructions from the running software, decode it, sends it to CPU for execution, which then stores any

data

Multitask by running multiple tasks at the same time

Input Control

Input: receives input from keyboard, mouse, touch screen, or any other input device

Output Control

Output: returns the results of processing to the display, printer, speakers, or other output device

Purposes of Input/Output Control Systems

Identify required IOCS services

Create control blocks for individual files

Process files

Identified Required IOCS Services

Supports several classes of I/O equipment Disk drives Tape drives Unit record equipment

Create Control Blocks for Files

Create codes to block specific files Each code is generated by a statement

Example of statements: DDF, DUF, CONSFILE

Process Files

They specify the actions that the system wishes to perform

This is done with processing macros

Types of Operating Systems

Embedded Operating Systems A system that is

hardwired into a computer component, such as a ROM or flash memory, to control a special purpose computer

Industrial Operating Systems A system that controls

large networked systems and servers

4 specific types of OS’s for a computer

Embedded Operating Systems

Used in many special purpose computers Typically are designed to perform a relatively

limited number of task Example: GPS

Optimized more easily which increases reliability and performance and reduces size and cost

Industrial Operating Systems

Much more complex manner than PC’s- require OS that can manage multiple processors Sometimes hundreds or thousands of processors, and

many users

Thank you!

Any Questions?