CompSci 4

Hardware

Physical components that make up computer

Software

Programs that run on the computer

System Software

Programs that enable computer to function

3 types of system software

OS system, utilities, programming language translators

Application Software

Programs that enable a user to perform tasks

4 types of application software

Word processors, spreadsheets, databases, ‘apps’

Operating Systems

Programs that manage computers resources, manages running applications

5 types of applications run by OS

Processors, memory, input/output devices, applications, security

Processor Management

Processor resources are managed by OS

What does the OS when running tasks?

Allocates slice of processor time for the various tasks needed to be run

OS and Memory Management

Programs are run in the main memory, OS manages where each program/data goes in memory

What do input devices do?

Input take real world data and convert it into a form that computers can store

What do output devices do?

Take input, proccess it and computer generates an output

How do OS manage I/O devices

I/O management controls sending of data (instructuon) to be printed from memory to device driver

What is a device driver?

a small program that acts as an interface between computer and device

What does application managment need?

Application programs need OS to function, OS runs a program to install applications

What does OS interact with applications through?

Applications Program Interface (API), which allows application to communicate with the OS

What does OS do with application storage?

Maintains a directory of where each application and each data file is stored on disk

What does OS do when applications are run?

Allocates a space in memory fro it to be loaded, job will enter queue of jobs being allocated processor time

How does OS provide security (4 functions:)?

Controlling access to a computer by using passwords for different users, setting different access rights and privilegews, automatically downloading updates for OS to ensure loopholes are patched, encrypting files stored on hard disk

What are embedded systems?

microprocessors/CPU’s, carry out simple/single functions, held in non-volatile memory, normally permanently stored/unable to upgrade hardware