Transcript Unit C: Computer Software

Computer Software
Unit C
Software Categories
Application Software
System Software
Software Categories
•Application Software helps you carry out taskssuch creating documents, editing photographs- using
a computer.
•System software helps your computer carry out
basic operating functions.
Software consists of computer programs, support
programs, and data files that work together to
provide a computer with the instructions and data
necessary for carrying out a specific type of task.
System Software
Operating
Systems
DOS
Windows
Mac OS
Linux
UNIX
Device
Drivers
Utilities
Programming
Languages
Application Software
Document
Production
Reference
Statistical
Spreadsheet
Software
Mathematical
Modeling
Entertainment
Data
Management
Accounting
& Finance
Music
Video
Educational
Graphics
Software Topics
Computer program
– main executable program (.exe)
Support module
– called by the program (.dll)
Data module
– Example: a dictionary file or a file that is
not supplied by the user
How Computers Interpret
Software
A programming or computer language provides
tools that a programmer uses to create software.
These languages help the programmer to
produce a list of instructions called source code.
The high-level languages are similar to human
languages and produce programs that are fairly
easy to test and modify.
Main programming languages include C++, Java,
COBOL, and Visual Basic,
How Computers Interpret
Software
A computer’s processor interprets the
programmer’s instructions, but the
processor can only understand machine
language.
Instructions written in a high-level
language must be translated into machine
language before a computer can use
them.
There are two types of translators:
compilers and interpreters.
How Computers Interpret Software
An interpreter coverts
one instruction at a
time while the
programming is
running.
How Computers Interpret
Software
•A compiler converts high-level instructions into a
Compiled program, which is a new file containing
machine language instructions.
•A complier translate all the instructions in a program
as a single batch, and the resulting machine
language instructions are placed in a new file. This is
the object code.
Operating Systems
Interacts with application
software, device drivers &
hardware to manage computers
resources
Exploring Windows
Starting programs
Creating and saving a document
with a text editor.
Creating files or directories
Moving and copying files with my
computer
Deleting an restoring files
Operating System Categories
A single-user operating system is designed to deal
with input, output, and processing requests from one
user.
PCs and handhelds
A multi-user operating system is designed to deal
with the input, output, and processing requests from
many users at the same time.
mainframes or centralized computer processing
A Network/Server operating system provides
communications and routing services that allow
computers to share data, programs and peripheral
devices.
Desktop: desktop or notebook PC; single-user, but
could handle networking
Operating System Categories
A multitasking operating system provides process
and memory management services that allow two or
more computer programs to run simultaneously.
Microsoft Windows is installed on over 80% of the
world’s PCs.
Mac OS
The UNIX operating system was developed in 1969
at AT&T’s Bell Labs. It gained a good reputation for its
dependability in multi-user environments.
In 1991, Linus Torvalds developed the Linux
operating system based on a version of UNIX. It is
very good and free!
DOS
Document Production Software
Use to compose, edit,
design, print or
electronically publish
documents
Types
– Word processing (Word)
– Desktop publishing
(PageMaker)
– Web authoring (Front Page)
Document Production Elements
Formatting
Page Layout
Headers/Footers
Clipart
Tables
Frames
Spell check
Word wrap
Margins
Styles
Spreadsheet Software
Use for numerical calculations and
graphs
Rows and columns
Worksheet, cell, cell references
Cells can contain
90
–
–
–
–
Values
Labels
Functions
Formulas
80
70
60
50
40
30
20
10
0
1st Qtr
2nd Qtr
3rd Qtr
4th Qtr
Spreadsheet Software
Formulas vs. functions
Relative vs. absolute cell
referencing
Automatic recalculation
Templates
What-if analysis
Data Management Software
Use to store, find, organize,
update and report information
File management software
– Structured or flat file
– A record contains multiple fields
Data Management Software
Database Management Software
(DBMS)
– Database (collection of related files)
– Relational (tables with records & fields)
– Object-oriented (records manipulated using
methods)
File structure
– Fields and data types
SQL (Structured Query Language)
– Natural query language
– Query by example (QBE)
Graphics Software
Use to create, display, modify,
manipulate and print graphics
Paint software: realistic art and
photos
Photo Editing software: simplifies
common editing tasks
Drawing software: uses vector figures
& shapes to create “cartoon-like”
images.
Graphics Software
3-D Graphics software:
create wireframes and then
cover with a texture
CAD (computer-aided
design): 3-D software
designed for architects and
engineers
Presentation software:
creates electronic slides like
these
Business Software
Accounting & Finance
– Personal finance
– Tax preparation
– Small business accounting
Vertical Market
– Hospitals, construction, schools
Horizontal Market
– Generic like payroll
– Project management
Groupware
– Help collaboration on group projects
License vs. Copyright
Software License: a legal contract
that defines the ways in which you
may use a computer program.
Copyright: a form of legal protection
that grants the author of an original
work an exclusive right to copy,
distribute, sell and modify that work.
Software piracy
For contract to take effect:
– Open a shrink-wrap license product
– Agree to an installation agreement
Types of Copyright Protections
Shareware: try before you
buy on the honor system
Freeware: no fee - can use,
but not alter or sell
Open Source: uncompiled
source code that can be
changed - sold or free
Public Domain: can be
copied, altered and resold
Computer Software
End