This document provides an introduction and overview of system analysis and design. It defines a system as a collection of interrelated components that function together to achieve an outcome. The key characteristics of a system are described as organization, interaction, interdependence, integration, and a central objective. The basic elements of a system are defined as inputs, outputs, processors, control, feedback, environment, and boundaries/interfaces. Different types of systems like physical/abstract and open/closed systems are discussed. The document also introduces system analysis and design, and different systems models like schematic, flow, static, and dynamic models. Recommended reference books on the topic are also provided.

1. Introduction
Introduction
System Analysis and Design
Khaled Hussain
BSc. Hons. (BCU, UK) MSc. (BCU, UK)
CEO, Cybernetics Robo Ltd.
www.cyberneticsrobo.com
(Ex. Head, Dept. of Computer Science & Engineering, SIU)

2. System Analysis and Design by Ellias M.
Awad
Software Engineering – A Practitioner’s
Approach (6th ed.) by Roger S. Pressman
Recommended Text
 Use of Internet is highly encouraged !

3. System
 A collection of interrelated components that function
together to achieve some outcome.
 Transportation system
 Telephone system
 Computer system
 Business system etc.
 A system is an orderly grouping of
interdependent components linked together
according to a plan to achieve one or more
objective

4. Characteristics of a system
 Organization
 Interaction
 Interdependence
 Integration
 Central Objective

5. Organization
 The arrangements of components that helps to achieve
objectives
 Implies structure and order
Characteristics of a system

6. Interaction
 Manner in which component functions with each
other. Ex. Purchasing must interact with production,
advertising with sales, and payroll with personnel.
Characteristics of a system

7. Characteristics of a system
Interdependence
 Coordinated and linked
together according to a
plan
 Parts or components of a system depending on
each other
Ex. A decision to computerize an
application is initiated by the user,
analyzed and designed by the
analyst, programmed and tested
by the programmer, and run by
the computer operator.

8. Characteristics of a system
Integration
 Concerned with how a system is tied
together
 How components of the system work
together to achieve the central objective
although each part performs a unique
function
Central Objective
 Main goal for producing a system
 If the correct objectives are not identified, the
correct problem will not be solved!

9. Elements of a system
 Outputs
 Inputs
 Processor(s)
 Control
 Feedback
 Environment
 Boundaries and Interface

10. Elements of a system
Outputs
 A major objective of a system is to produce an
output
 The output may be goods, services or information.
It should satisfy the expectations of the user.
Inputs
 Inputs may be material, human resources,
information that enters the system for
processing.

11. Processor(s)
 The element of a system that involves the
actual transformation of input into output.
 Processors may modify the input totally or
partially depending on the specifications of the
output.
Control
 The control element guides the system
Elements of a system
 Management as a decision-making body
controls the inflow, handling, and outflow
of activities that affect the business.

12. Feedback
 Control in a dynamic system is achieved by
feedback.
 Feedback may be positive or negative, routine or
informational.
Elements of a system
 Positive feedback reinforces the performance of the
system.
 Negative feedback generally provides the controller
with information for action.

13. Environment
 The environment is the supra system within
which an organization operates.
 The organization environment consists of vendors,
competitors, and others, which provides constraints
and influences the actual performance of the business.
Elements of a system

14. Boundaries & Interfaces
 A system has a boundary, within which all of its
components are contained and which establishes
the limits of a system, separating it from other
systems.
Ex. A teller system in a commercial bank is restricted to its
deposits, withdrawals and related activities of customers’
accounts.
Elements of a system
 The point at which the system meets its environment
are called interface.

15. Elements of a system

16. System Analysis & Design
A systematic investigation of a real or planned system to
determine the functions of the system and how they relate to
each other and to any other system.
Systems Analysis is understanding and specifying in detail
what an information system should do.
System Design is specifying in detail how the parts of an
information system should be implemented.

17. Types of systems
 Physical or Abstract Systems
 Open or Closed Systems
 ‘Man-made’ Information Systems

18. Physical Systems
 Tangible entities that may be static or dynamic in
operation.
Ex. The physical parts of the computer center are the offices,
desks, and chairs that facilitate operation of the computer.
These are static. On the other hand, a programmed computer
is a dynamic system.
Types of systems

19. Abstract Systems
 Abstract systems are conceptual or nonphysical
entities.
Types of systems
 May be as formulas of relationships among sets of
variables or models.

20. Open or Closed Systems
 An open system has many interfaces with its
environment and permits interaction across its
boundary. Ex. Information system.
Types of systems
 Closed systems refer to systems having relatively
little interaction with other systems or the outside
environment. Ex. A watch.

21. Man-made Information Systems (Computer-Based)
Types of systems
An information system is an arrangement of people, data,
processes, interfaces, networks, and technology that interact for
the purpose of supporting and improving both day-to-day
operations in a business as well as supporting the problem
solving and decision making needs of management.

22. Man-made Information Systems (Computer-Based)
 Management Information System (MIS)
Types of systems
Systems that take information and produce reports that
management needs for planning and controlling the
business.
 Decision Support System (DSS)
Allow a user to explore the impact of available options or
decisions.
Whereas an MIS produce reports, DSS provide an
interactive environment in which decision makers can
quickly manipulate data and models of business
operations.

23. Systems Models
Reason for Modeling
 Highlight problems of interest.
 Economical experimentation.
 Precision of thought.
A model is a representation of an existing or a
planned system.
 Solving operational problems.
 Visualize overall system etc.

24. Systems Models
 Schematic Models
 Flow System Models
 Static Systems Models
 Dynamic Systems Models
A model is a representation of a existing or a planned
system.

25.  Schematic Models
A schematic model is a two-dimensional chart depicting
system elements and their linkages. It provides a
means of visualizing system structure and operation
Systems Models

26.  Flow System Models
A flow system model shows the flow of the material,
energy and information that hold the system together.
There is an orderly flow of logic in such models.
Systems Models
A widely known example is
PERT (Program Evaluation
and Review Technique).

27.  Static System Models
Exhibits one pair of relationships such as activity-time
or cost-quantity. Ex. Gantt Chart.
Systems Models
 Dynamic System Models
Approximates the type of organization or applications
that the analysts deal with. It depicts on ongoing,
constantly changing system. Ex. Business
organizations.

28. References
References
 Awad E. M., System Analysis and Design (2nd ed.)