Transcript Document - Oman College of Management & Technology

Chapter 2
INTRODUCTION OF
SYSTEM & APPLICATION
SOFTWARE
Dr. BALAMURUGAN MUTHURAMAN
2015-2016
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OPERATING SYSTEM (OS)
An operating system, or OS, is a software program that
enables the computer hardware to communicate and operate
with the computer software. Without a computer operating
system, a computer would be useless.
 A collection of programs which control the resources of a
computer system
 Written in low-level languages (i.e. machine-dependent)
 An interface between the users and the hardware
 When the computer is on, OS will first load into the main
memory
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BASIC FUNCTIONS OF THE
OPERATING SYSTEM
Device configuration
Controls peripheral devices connected to the computer
File management
Operating
System
Transfers files between main memory and secondary storage,
manages file folders, allocates the secondary storage space,
and provides file protection and recovery
Memory management
Allocates the use of random access memory (RAM) to
requesting processes
Interface platform
Allows the computer to run other applications
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OTHER FUNCTION OF
OPERATING SYSTEM
• Best use of the computer resources
• Provide a background for user’s programs to
execute
• Display and deal with errors when it happens
• Control the selection and operation of the
peripherals
• Act as a communication link between users
• System protection
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TYPES OF OPERATING SYSTEM
»Graphical User Interface (GUI)
»Multi-user
»Multiprocessing
»Multitasking
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GUI - Short for Graphical User Interface, a
GUI Operating System contains graphics and
icons and is commonly navigated by using a
computer mouse.
Multi-user - A multi-user operating system
allows for multiple users to use the same
computer at the same time and different
times.
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Multiprocessing - An operating system
capable of supporting and utilizing more than
one computer processor.
Multitasking - An operating system that is
capable of allowing multiple software
processes to run at the same time.
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SYSTEM SOFTWARE
The programs and the file that comprises the
operating system are called system software. These
files include configuration files, system
preferences, system services, libraries of functions
and the drivers for the hardware installed on the
computer. Once you install the operating system,
the system software is also installed. Program such
“Software update” or “Windows update” can be
used to update the system software.
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APPLICATION SOFTWARE
The subclass of a computer program which
utilizes the capabilities of computer is called
application software. Application here means
the
application
software
and
the
implementation. The example of application
software programs includes media players,
spreadsheets and word processors. When
multiple applications are packaged together
then it is called application suite.
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There is a common user interface in each
application suite which makes it easier for
the user to learn different applications. In
some cases, such as Microsoft Office, the
various application programs have the
ability to interact with each other. This
facility is very handy for the user. For
example, a user can insert the spreadsheet in
a word processor using the application
software. Application software cannot run
without the presence of system software.
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DIFFERENCE BETWEEN SYSTEM SOFTWARE
AND APPLICATION SOFTWARE
• System software gets installed when the
operating system is installed on the computer
while application software is installed
according to the requirements of the user.
• System software includes programs such as
compilers,
drivers,
assemblers
while
application software includes media players,
word processors, and spreadsheet programs.
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• Generally, users do not interact with system
software as it works in the background whereas
users interact with application software while
doing different activities.
• A computer may not require more than one type
of system software while there may be a number
of application software programs installed on
the computer at the same time.
• System software can run independently of the
application software while application software
cannot run without the presence of the system
software.
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Data Base Management Systems (DBMS)
• A database is a collection of information
categorized by specific fields. Databases are
usually searchable by keywords.
• A collection of related electronic records in a
standardized format, searchable in a variety of
ways, such as title, author, subject, and keyword.
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DEFINITION -DBMS
A Database Management System (DBMS)
is a set of computer programs that controls
the creation, maintenance, and the use of the
database of an organization and its end users
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Example of DBMS
A database is any organized collection of data.
Some examples of databases you may
encounter in your daily life are:
– a telephone book
– T.V. Guide
– airline reservation system
– motor vehicle registration records
– papers in your filing cabinet
– files on your computer hard drive.
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Purpose of DBMS
Keep records of our:
Clients
Staff
Volunteers
To keep a record of activities and
interventions;
Keep sales records;
Develop reports;
Perform research
Longitudinal tracking
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Drawbacks of using file systems to store data:
– Data redundancy and inconsistency
• Multiple file formats, duplication of information in
different files
– Difficulty in accessing data
• Need to write a new program to carry out each new
task
– Data isolation — multiple files and formats
– Integrity problems
• Integrity constraints (e.g. account balance > 0)
become part of program code
• Hard to add new constraints or change existing ones
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Why Use a DBMS?
•
•
•
•
•
Data independence and efficient access.
Reduced application development time.
Data integrity and security.
Uniform data administration.
Concurrent access, recovery from crashes.
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