Transcript European Computer Driving Licence

European Computer Driving
Licence
Module 1 – Concepts of IT
Chapter 1.3 - Software
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1
What is software?
Z Primarily a list of instructions coded in a special way
that computers can understand
,
,
Operating system software – eg Windows which works in the
background and controls your software and hardware devices
Applications software – eg Microsoft Word – software used to
perform tasks
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Software Updates
Z Software is constantly
updated to give the user
improved features
Z Most software manufacturers
will provide updates to solve
problem issues
Z Software manufacturers will
provide new versions to
comply with new operating
systems
Z Be careful with software
versions – a file created in
Word 2003 may not be
opened on a PC running
Word 97
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Operating System Software
Z Series of programs that
organise and control a
computer
,
,
,
,
Manages the smooth
running of programs running
in RAM by allocating the
required resources
Provides an interface so that
the user can communicate
with the computer
Communicates between
software and hardware
devices
Organises the storage and
retrieval of information
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Popular Operating Systems
Z Microsoft Windows is the
most widely-used operating
system (OS)
Z OS2 is an OS created by IBM
Z Macintosh (MacOS) was
created by Apple
Z Linux is a popular alternative
open-source OS
Z MS-DOS was precursor of
Windows but text-based
Z Unix is another OS used in
companies or universities
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Graphical User Interface
Z Enables users to click and point at icons and menus on screen,
instead of typing in computer commands
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Applications Software
Z Word processor – used for typing letters, memos, reports etc
Z Spreadsheet – used for performing calculations (eg Accounts)
and for creating Charts
Z Database – used for storing large quantities of data which can be
interrogated to display specified pieces of information
Z Desktop Publishing – used for creating newsletters, booklets,
posters, cards etc
Z Presentation – used for creating presentations which can either
be displayed on screen, or printed onto overhead projection film
or 35 mm slides.
Z Web browsers – allows users to view and download information
from the world wide web
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Examples of Application Software
Z Microsoft Office – which
comprises:
,
,
,
,
,
,
,
Z Internet Explorer / Netscape
Navigator / Mozilla / Opera
Word (word processing)
Excel (spreadsheet)
Access (database)
PowerPoint (presentation)
Publisher (desktop
publishing)
Outlook (e-mail software)
Frontpage (web page
creation)
(web browsers)
Z CorelDraw! (graphics)
Z Sage (accounts and payroll)
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Systems Development
Z Computer-based systems are developed by specialist
teams of system analysts and programmers
Z Development of large computer-based systems can
involve dozens of people working over a few months
or even years
Z Formal methods and procedures are applied to
ensure the project is delivered on time
Z This process is known as the Systems Life Cycle
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The Systems Life Cycle
Analysis
Evaluation
Design
Programming
Testing
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The Different Stages
Z Analysis
,
When the need for a computer system is identified, a systems
analyst will analyse the requirements – how will information be
input? What processing is required? What output is required?
Z Design
,
The overall system is designed with each subsection in fine detail,
including screen layouts, user interfaces, format of stored data,
processing and output
Z Programming
,
A team of programmers will each work on a module of the final
package.
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The Different Stages (cont’d)
Z Testing
,
Each section is tested individually and then as part of the
whole suite. Data is supplied (including ‘normal’ and
‘erroneous’) to test the system to make sure it is stable.
Z Evaluation
,
,
Once the system has been put into operation, it must be
evaluated to see how well it performs.
A new system may be needed and the whole process starts
again
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