1. Computer Software
Mr Arthur

2. Aims of Lesson 1
1. Go over Network test
2. What is an Operating
System?
3. Application Software

3. Operating System
 The OS is the program that provides the HCI, manages
input and output and controls all Main Memory and
Backing Storage devices
 The Bootstrap is a program that loads the OS from
Backing Storage
 Examples
 Windows XP/Vista/7/MACOS/Linux
 Key functions
 Providing the HCI
 Displaying data on screen
 Creates Hierarchical filing system
 Saving files to backing storage
 Provides security
 Controls input/output devices

4. Application Software (Apps)
 Application software does not control parts of
the computer but is written to the help the
user perform a particular task
 Examples
 Microsoft Word
 Microsoft Excel
 Itunes
 Powerpoint

5. Lesson Starter
1. What is an Operating System?
2. Give 3 functions on an Operating System
3. What is Application software?

6. Aims of Lesson 2
Last Lesson
1. What is an Operating
System?
2. Application Software
Today’s Lesson
1. Standard File
Formats
2. Objects and
Operations

7. Standard File Formats
 A Standard File Format is a file format that
can be opened up on many different
applications
 Text
 ASCII, txt, Rich Text Format
 Graphics
 JPEG, Bitmap, Gif

8. Objects and Operations
Application Object Operation
Word Processing Letter/Word Format Size/Style/Cut/Paste/Align
Graphics Image Crop/Rotate/Rescale
Spreadsheet Text/Number Format Size/Cut/Paste/Align
Database Field/Record Change Field Type/Sort/Search

9. Aims of Lesson 3
Last Lesson
1. What is an Operating
System?
2. Application Software
3. Standard File Formats
4. Objects and Operations
Today’s Lesson
1. Computer Virus
2. Symptoms of a Virus
3. How they Spread
4. Antivirus

10. Computer Virus
 A virus is a destructive piece of software that
attaches itself to other files, reproduces, spreads
and corrupts files or data
 Virus Symptoms
 Strange noises or visual effects
 Unexpected reboot of computer
 Unwanted creation of emails
 Displaying unwanted messages
 How they Spread
 Spread through infected memory sticks, cds
 Visiting infected websites and downloading code
 Downloading infected email attachments

11. Antivirus Software
 Anti-virus software often works by having a
database of virus signatures (parts of code that
are viruses)
 The software then scan documents, files etc
comparing them to the virus signatures
 The software then flags up the virus it has
found
 Antivirus software needs to be constantly
updated to add new virus signatures to the
database

12. Arrangements
 Distinction between an operating system and an application program with
examples of each
 Explanation of the need for standard file formats
 Description of the following standard file formats for text files: text, ASCII,
rich text file
 Identification of data objects and operations in the context of word
processing, databases, spreadsheets and graphic packages
 Definition of a virus
 Description of how a virus operates
 Description of the following common symptoms of virus infection: displaying
unwanted messages, unusual visual/sound effects, computers rebooting
unexpectedly, unwanted generation of e-mails
 Description of how viruses are spread via floppy disk, homemade CDs, ‘fun’
websites and e-mail attachments
 Explanation of the need for anti-virus software