Lecture 4:Software

Tonga Institute of Higher EducationIT 141: Information Systems

Introduction

Computer software determines the tasks a computer can help you get

Software helps you Create documents Block viruses Make your computer’s performance better

Software Categories Computer program: instructions that tell a

comp how to carry out at task These programs software Software prepares a comp to do a specific

task (e.g. photo editing, virus protection, file management, or Web browsing)

Programs are written in a computer language that the computer can understand.

Typical languages might be called C, C++, Java

Software Categories

Application Software

Also known as an application or app Examples:

Productivity software Groupware: designed to help several people

collaborate on a single project using local networks or Internet connections

Utility Software

Help monitor and configure settings for comp system equipment, the OS, or the application software

E.g. setup wizards, security software, diagnostic tools

Desktop widgets: desktop widgets include clock, calendars, sticky notes, etc.

Device Drivers

Software that helps a peripheral device start communication with a computer

For printers, screens, modems, storage devices, scanners, sound cards etc.

Document production software

Word processing software: MO Word Desktop publishing software Spreadsheet software: MO Excel Statistical software Database Software: MO Access

Database Software

Database: collection of data that is stored on one or more computers

Database software helps you enter, find, organize, update and report information in a database.

Record holds data for a single entity Field holds one item of data relevant to

a record

Other application software Graphics Software: Microsoft Paint,

Adobe Photoshop Music Software Video Editing and DVD authoring Educational and Reference Entertainment Business

Buying software Essential applications

OS, browser, word processing, security suite, graphics viewer, drivers, entertainment.

Should ONLY have one security software Check system requirements Copyright: form of legal protection that

grants the author of an original work an exclusive right to copy, distribute, sell, and modify that work,

Software license

Software license: agreement Single-user license limits use to one person at

a time Site license allows software to be used on all

computers at a specific location Multi-user license: allows allocated number of

people to use the software at any time Concurrent-use license allows a specific

number of copies to be used at the same time

Different software licenses

Public domain software Proprietary software Commercial software Demoware Shareware Freeware Open source software

Installing Software and Upgrades

Inside a software package there is an executable file with an .exe file extension, support programs with a .dll file extension, data files and sometimes share some common files with other software. This can be supplied by the OS.

.exe

.txt.bmp.hlp

Processor

.dll.ocx

Installing Software and Upgrades

Software Installation

Software installation: process that places a program into a computer so it can be used (run or executed)

Installation procedures depend on the computer’s operating system and whether the software is a local, Web, or portable application.

Local Application

Local Application: software that is designed to stay on a computer’s hard disk.

Most local applications contain a setup program to show you how to install

Windows Registry

This is database that keeps track of your computer’s peripheral devices, software, preferences, and settings.

When you install software on the hard disk, information about the software is recorded in Registry.

This is a means of protecting software from illegal copying It requires users to enter a product key or activation code Can be activated over the phone or Internet

Product activation

Portable Software

It is made to run from removable storage such as a CD or USB flash drive

Program files do not exist on the hard disk

E.g. – Thunderbird (e-mail)

Web Application (Web app)

Software that is accessed with a Web browser

E.g. – Gmail, Yahoo!, Google Earth

Software Updates

Software publishers regularly update their software to add new features, fix bugs, and update its security

Types of software updates include new versions, patches, service packs.

Software updates

Software patches: small section of program code that replaces part of the software you currently have installed

Service pack is a set of patches that correct problems and address security vulnerabilities.

They are usually free

Uninstalling software

DOS – remove by deleting its files Windows and Mac OS – uninstall routine

which deletes the software’s files from various folders on your computer’s hard disk

Security software basics

Security software – protect comps from various forms of destructive software and unauthorized intrusions

Different types – antivirus, anti-spyware, anti-spam, and firewalls

Malware software

Any computer program designed to surreptitiously enter a computer, gain unauthorized access to data, or disrupt normal processing operations.

Viruses, worms, Trojans, bots, and spyware

Malware software

Created by hackers, crackers, black hats, or cybercriminals

Annoy, disrupt operations, identity theft, or organized crimes

Computer virus

Set of program instructions that attaches itself to a file, reproduces itself, and spreads to other files

Viruses DO NOT spread themselves from one computer to another

Signs – displaying annoying messages to corrupting data on the hard disk

Computer worm

Self-replicating program designed to carry out some unauthorized activity on a victim’s computer

Can spread themselves from one computer to another without any assistance from victims

Mass-mailing worm spreads by sending itself to every address in the address book of an infected comp

Trojan horse (Trojan)

Computer program that seems to perform one function while actually doing something else.

Unlike a worm a Trojan is NOT designed to spread itself to other computers

Not designed to replicate

Trojan horse

Keylogger – steal password Remote Access Trojan – allow remote

hackers. Using a victim’s computer as a relay station for breaking into other computers

Bot / intelligent agent

Software that can automate a task or autonomously execute a task when commanded to do so

Behaves like a robot so it is often called bot Good bots – helpful Bad bots (zombies) – destructive Botnet – network of bot-infested comps

Spyware

Type of program that secretly gathers personal information without the victim’s knowledge, usually for advertising and other commercial purposes

What does malware do?

Carry out a variety of unauthorized activities

How do you know if your comp is infected? Irritating messages or sounds Frequent pop-ups Slower response Missing files etc.

Rootkit and virus hoax

Rootkit - Software tools used to hide malware and backdoors that have been installed on a victim’s computer.

Virus hoax – warnings about a supposedly new virus on the loose

Security Suites

Combines several security modules to protect against the most common types of malware, unauthorized access, and spam.

E.g. – Norton 360

Antivirus modules

Type of utility software that looks for and eradicates viruses, Trojan horses, worms, and bots.

How does it work? Software scans for virus signatures in

programs, data files, incoming/outgoing emails and attachments, and inbound instant message attachments.

Antivirus modules

Antivirus software periodically need to be updated Might need a patch or update to fix bugs or

improve features List of virus signatures has to be updated to

keep up with the latest malware developments Virus definition – files that store virus signature

and other information used to erase malware

Antivirus modules

Use Antivirus to scan your computer frequently

Make sure that the virus signature is up to date

Summary

Software Application software Installing software The Window Registry Copyrights Malware Antivirus