COMPUTER SYSTEMS
Batch Processing System:
Definition: Batch processing is a computer processing model in which data is collected,
processed, and stored in batches or groups. It contrasts with real-time or interactive systems
where data is processed immediately upon input.
Examples:
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Payroll processing: Employee time records are collected over a pay period, and salaries
are calculated and distributed in a batch process.
Billing systems: Utility companies generate customer invoices based on meter readings
and usage data in batch cycles.
Report generation: Large reports, such as financial statements or inventory reports, are
generated periodically in batch processes.
Batch data updates: Database systems perform data updates, backups, and maintenance
tasks during non-peak hours.
Characteristics:
1. Sequential Processing: In batch processing, tasks or jobs are executed sequentially, one
after another. Each job is processed in its entirety before the next one begins.
2. Offline Processing: Batch jobs are often submitted and processed offline, without direct
user interaction. Users typically submit their jobs, and the system processes them at a
later time.
3. Scheduled Execution: Batch jobs are often scheduled to run at specific times or during
non-business hours to minimize disruptions to users and system resources.
4. Data Collection and Processing: Data is collected over a period and then processed as a
group. For example, in a payroll batch processing system, employee time records are
collected over a pay period and processed together to calculate salaries.
5. Job Queuing: Batch jobs are placed in a queue, awaiting their turn for processing. The
order of execution can be determined by priorities or scheduling rules.
6. Error Handling: Batch processing systems typically include error handling mechanisms
to detect and manage errors that may occur during job processing. Failed jobs can be
rerun or flagged for review.
Advantages:
1. Efficiency: Batch processing is efficient for handling large volumes of data and repetitive
tasks. It can optimize resource utilization by processing tasks in bulk.
2. Resource Management: Batch jobs can be prioritized and scheduled based on their
importance and resource requirements, allowing for efficient resource allocation.
3. Data Integrity: Batch processing is well-suited for tasks that require high data integrity
and consistency, such as financial transactions and data reconciliation.
Disadvantages:
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1. Latency: Batch processing can introduce delays in processing, as jobs are queued and
executed one by one. This may not be suitable for real-time or time-critical applications.
2. Limited Interactivity: Batch processing is not well-suited for interactive or user-driven
applications where immediate responses are required. Users must wait for batch jobs to
complete.
3. Complex Job Scheduling: Managing and scheduling batch jobs can be complex,
especially in large-scale systems with many jobs and dependencies.
Batch processing systems are valuable for tasks that can be automated and do not require
immediate responses. They are commonly used in business and enterprise applications where
data accuracy and resource optimization are priorities.
Interactive Systems:
Interactive systems are computer-based systems designed to allow users to interact with digital
technology, software applications, or hardware devices in real-time. These systems are
characterized by their responsiveness to user input and their ability to provide immediate
feedback or results. Interactive systems are used in a wide range of applications, from web
browsing and video games to word processing and scientific simulations. Here's a detailed
overview of interactive systems:
Characteristics:
1. Real-Time Interaction: Interactive systems provide real-time responses to user inputs.
When users perform actions, such as clicking a button or entering data, the system
responds promptly.
2. User Interface: They typically include user-friendly interfaces that facilitate user
interaction. These interfaces can be graphical (GUI), command-line, or voice-controlled,
depending on the system's design.
3. User Input: Users interact with interactive systems through various input methods, such
as keyboards, mice, touch screens, voice commands, and gestures.
4. Multimedia Elements: Many interactive systems incorporate multimedia elements,
including text, images, audio, and video, to engage users and convey information.
5. Application Diversity: Interactive systems are used in a wide range of applications,
including software applications, video games, educational tools, simulations, and virtual
reality environments.
Advantages:
1. User Engagement: Interactive systems offer a high level of user engagement and
responsiveness, enhancing the user experience and promoting user participation.
2. Real-Time Feedback: Users receive immediate feedback, which is especially valuable in
applications where user actions have consequences or influence outcomes.
3. Interactivity: They enable two-way communication between users and technology,
allowing users to control and influence the system's behavior.
Disadvantages:
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1. Performance Demands: Interactive systems require efficient processing and fast
response times. Performance issues can lead to user frustration.
2. Maintenance: Continuous monitoring and maintenance are necessary to ensure that
interactive systems remain responsive and reliable.
3. Complexity: Designing and developing interactive systems can be complex, particularly
for applications with advanced features and interactions.
Examples of Interactive Systems:
1. Web Browsers: Web browsers, such as Google Chrome and Mozilla Firefox, allow users
to browse the internet, click on links, fill out web forms, and interact with web-based
content.
2. Video Games: Video game consoles and PC games are prime examples of interactive
systems. Players control characters, solve puzzles, and make decisions that impact the
game's storyline and outcomes.
3. Smartphones and Mobile Apps: Smartphones and mobile apps offer various interactive
experiences, from social media interactions to mobile gaming and productivity apps.
4. Word Processing Software: Applications like Microsoft Word and Google Docs enable
users to create, edit, and format text documents with interactive features like spellchecking and real-time collaboration.
5. Educational Software: Interactive educational software and e-learning platforms
provide students with interactive lessons, quizzes, and simulations to enhance learning.
6. Simulation Software: In scientific and engineering fields, simulation software allows
users to interact with virtual models, perform experiments, and analyze outcomes.
7. Virtual Reality (VR) and Augmented Reality (AR) Systems: VR and AR systems
immerse users in interactive 3D environments and overlay digital information on the
physical world, respectively.
Interactive systems have transformed the way people interact with technology, making it more
intuitive and engaging. Their versatility and user-centric design principles have contributed to
their widespread use in a variety of domains, including entertainment, education,
communication, and productivity.
Automated System:
An automated system is a computer-controlled or mechanical system that performs tasks or
processes with minimal human intervention. These systems rely on pre-programmed instructions
or algorithms to execute operations, often repeatedly and consistently. Automation is widely
used across various industries to improve efficiency, reduce errors, and save labor costs. Here's a
detailed overview of automated systems:
Examples of Automated Systems:
1. Manufacturing Robots: Industrial robots perform tasks such as welding, painting, and
assembly in manufacturing plants.
2. Automated Teller Machines (ATMs): ATMs automate cash withdrawal and deposit
processes in banking.
3. Automated Warehousing Systems: These systems use robots and conveyors to handle
inventory, pick orders, and prepare shipments.
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4. Automated Vacuum Cleaners: Robot vacuum cleaners navigate and clean floors
autonomously.
5. Automated Trading Systems: In financial markets, automated trading systems execute
buy and sell orders based on predefined algorithms.
6. Automated Medical Devices: Devices like automated blood analyzers and surgical
robots assist healthcare professionals in diagnostics and procedures.
Characteristics:
1. Task Automation: Automated systems are designed to perform specific tasks or
processes automatically, following predefined instructions. These tasks can range from
simple to complex.
2. Minimized Human Intervention: Automation reduces the need for direct human
involvement in the execution of tasks. Human operators may only be required for
supervision, monitoring, or handling exceptions.
3. Consistency: Automated systems consistently perform tasks without fatigue or errors.
They follow the same set of instructions every time, ensuring reliability and repeatability.
4. Sensors and Feedback: Many automated systems incorporate sensors to gather data and
provide feedback to the control system. This feedback helps the system make real-time
adjustments.
5. High Speed: Automation often results in faster task execution compared to manual
processes. This is particularly beneficial in manufacturing and production environments.
Types of Automated Systems:
Automated systems can take various forms based on their applications and functions:
1. Industrial Automation: Used in manufacturing and production facilities to automate
processes such as assembly, quality control, and material handling. Examples include
robotic arms and automated conveyor systems.
2. Home Automation: In smart homes, automation systems control aspects like lighting,
heating, cooling, security, and entertainment, enhancing convenience and energy
efficiency.
3. Office Automation: Office automation systems streamline administrative tasks,
including document management, scheduling, and communication. Examples include
email automation and document scanners.
4. Process Automation: In chemical and petrochemical industries, process automation
systems manage complex chemical processes, ensuring safety and efficiency.
5. Retail Automation: Automation is used in retail for tasks like inventory management,
self-checkout systems, and order fulfillment in e-commerce warehouses.
6. Agricultural Automation: Agricultural automation involves the use of automated
machinery for tasks like planting, harvesting, and irrigation in farming.
7. Healthcare Automation: In healthcare, automation systems are used for tasks such as
medical imaging, medication dispensing, and laboratory analysis.
Advantages of Automated Systems:
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1. Precision: Automated systems perform tasks with high precision, reducing errors and
inconsistencies.
2. Efficiency: Automation increases operational efficiency by executing tasks quickly and
consistently.
3. Cost Savings: Automated systems can reduce labor costs, improve resource utilization,
and lower the risk of human error, resulting in cost savings.
4. Safety: In hazardous or dangerous environments, automated systems can operate without
exposing humans to risks.
Disadvantages of Automated Systems:
1. Initial Setup: Designing and implementing automation systems can be costly and timeconsuming.
2. Maintenance: Automated systems require regular maintenance to ensure proper
functioning, and system failures can be complex to diagnose and repair.
3. Lack of Adaptability: Some automated systems may struggle to adapt to unexpected or
complex situations that require human judgment.
Automated systems have revolutionized various industries by enhancing productivity, reducing
costs, and improving safety. They continue to play a significant role in increasing efficiency and
precision in today's automated and interconnected world.
Multimedia Systems and Applications:
Multimedia systems and applications refer to computer-based systems and software that integrate
various forms of media, including text, images, audio, video, animations, and interactive
elements, to create rich and engaging user experiences. These systems and applications are used
across a wide range of fields, including entertainment, education, communication, and business.
Here's a detailed overview of multimedia systems and applications:
Characteristics:
1. Media Integration: Multimedia systems seamlessly integrate multiple types of media,
such as text, images, audio, video, and animations, to create immersive and interactive
content.
2. Interactivity: Many multimedia applications offer interactivity, allowing users to engage
with the content by clicking, dragging, typing, or using gestures. This interactivity
enhances user engagement and participation.
3. Playback and Presentation: Multimedia systems provide mechanisms for playing back
or presenting multimedia content. This can include media players, web browsers,
presentation software, and more.
4. Content Creation: Multimedia applications often include tools for content creation,
enabling users to author and edit multimedia content. Examples include graphic design
software, video editors, and 3D modeling tools.
5. Streaming: With the advent of high-speed internet, multimedia systems often
incorporate streaming capabilities, allowing users to access and view content in real-time
over the internet.
6. Data Compression: Multimedia systems employ various data compression techniques to
reduce the size of media files, enabling efficient storage and transmission.
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Advantages:
1. Engagement: Multimedia systems enhance user engagement and communication by
providing a multisensory experience. This is especially valuable in education,
entertainment, and marketing.
2. Creative Content: Multimedia applications empower users to create and share creative
content, from videos and animations to interactive presentations and games.
3. Information Delivery: They facilitate the effective delivery of complex information by
combining text, images, and videos to convey messages more comprehensively.
4. Entertainment: Multimedia systems are a cornerstone of the entertainment industry,
providing a platform for video games, streaming services, virtual reality experiences, and
more.
Disadvantages:
1. Resource Demands: High-quality multimedia, especially videos and animations, require
substantial storage and processing resources, which can be costly.
2. Compatibility Issues: Multimedia content may face compatibility challenges across
different devices, platforms, and web browsers, requiring additional development efforts.
Examples of Multimedia Systems and Applications:
1. Video Streaming Services: Platforms like Netflix, YouTube, and Hulu provide users
with access to a vast library of multimedia content, including movies, TV shows, and
user-generated videos.
2. Video Games: Video games use multimedia elements, including 3D graphics, sound
effects, and music, to create immersive gaming experiences.
3. E-Learning Platforms: Educational platforms incorporate multimedia components such
as videos, interactive simulations, and quizzes to enhance online learning.
4. Graphic Design Software: Applications like Adobe Photoshop and Illustrator enable
users to create and edit images and graphics for various purposes.
5. Virtual Reality (VR) Experiences: VR systems immerse users in multimedia-rich
virtual environments for gaming, training, and simulations.
6. Interactive Presentations: Tools like Microsoft PowerPoint and Prezi allow users to
create multimedia-rich presentations with text, images, animations, and videos.
7. Augmented Reality (AR) Apps: AR apps overlay digital information, such as 3D
models or annotations, onto the physical world, enhancing user experiences.
8. Social Media Platforms: Social media platforms like Facebook, Instagram, and TikTok
enable users to share multimedia content, including photos, videos, and live broadcasts.
Multimedia systems and applications have transformed how information is presented and
consumed. They are integral to modern communication, entertainment, education, and
marketing, providing users with engaging and interactive experiences across various digital
platforms.
Network System:
A network system refers to a collection of interconnected computers, devices, or components
that communicate and share resources with one another over a network. Network systems are
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fundamental in today's digital world and play a crucial role in enabling data exchange,
communication, and resource sharing among devices, users, or systems. Here's a detailed
overview of network systems:
Characteristics:
1. Resource Sharing: Network systems allow connected devices to share various resources,
including files, printers, databases, and internet access. This facilitates collaboration and
efficient resource utilization.
2. Data Communication: Devices within a network can exchange data and information.
This data can be in the form of text, files, images, videos, or any other digital content.
3. Interconnectivity: Network systems provide the means to connect devices, often through
wired (e.g., Ethernet) or wireless (e.g., Wi-Fi) connections. Networks can range from
local area networks (LANs) within a single building to wide area networks (WANs) that
span large geographic areas.
4. Protocols and Standards: Network systems rely on standardized protocols and
communication rules to ensure that data can be transmitted and received reliably.
Common network protocols include TCP/IP (for internet communication), HTTP/HTTPS
(for web browsing), and SMTP/POP3 (for email).
5. Remote Access: Networks enable remote access to resources and systems. Users can
access data and applications from remote locations, which is crucial for remote work,
telecommuting, and global connectivity.
6. Security Measures: Security is a critical aspect of network systems. They employ
various security measures, including firewalls, encryption, access control, and intrusion
detection systems, to protect against unauthorized access and data breaches.
Types of Network Systems:
Network systems can take various forms based on their scope, purpose, and scale:
1. Local Area Network (LAN): A LAN is a network confined to a relatively small
geographic area, such as a home, office, or campus. LANs are commonly used for local
resource sharing and internet connectivity.
2. Wide Area Network (WAN): A WAN spans a larger geographical area and connects
LANs or other networks. The internet itself is a vast global WAN that interconnects
networks worldwide.
3. Client-Server Network: In a client-server network, multiple clients (user devices)
connect to one or more centralized servers that provide services or resources. This
architecture is common in business environments for tasks like file sharing, email, and
web services.
4. Peer-to-Peer (P2P) Network: In a P2P network, devices are equal peers that can both
request and provide resources directly to one another. P2P networks are often used for
file sharing and collaborative applications.
5. Cloud Computing: Cloud computing leverages network systems to deliver computing
services and resources over the internet. Users access cloud-hosted applications and data
from anywhere with an internet connection.
Advantages of Network Systems:
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Efficient Data Exchange: Network systems facilitate efficient data exchange, reducing
the need for physical data transfers.
Resource Sharing: They enable resource sharing, reducing redundancy and improving
collaboration.
Remote Access: Users can access resources and services remotely, promoting flexibility
and productivity.
Scalability: Network systems can be scaled to accommodate growing data and user
requirements.
Disadvantages of Network Systems:
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Security Concerns: Network systems are vulnerable to security threats, including data
breaches, malware, and unauthorized access.
Downtime Risks: Network downtime or failures can disrupt operations, emphasizing the
need for reliability and redundancy.
Complexity: Managing and maintaining network systems can be complex, especially in
large-scale environments.
Network systems are the backbone of modern communication and information exchange. They
are integral to businesses, organizations, and individuals, enabling connectivity, collaboration,
and access to a wide range of digital resources.
CONTROL SYSTEMS
A control system is a computer-based or mechanical system that manages, directs, or regulates
the behavior of other systems, devices, or processes to achieve desired outcomes or maintain
specified conditions. Control systems are used in various fields, including industrial automation,
robotics, automotive engineering, and more. Here's a detailed overview of control systems:
Characteristics:
1. Feedback Mechanism: Control systems typically employ a feedback mechanism to
continuously monitor the output or behavior of a system and make adjustments based on
the difference between the desired or reference value and the actual value (error).
2. Automation: Control systems are designed to automate processes or tasks, reducing the
need for human intervention. They can operate autonomously based on predefined rules
or algorithms.
3. Sensors and Actuators: Control systems rely on sensors to collect data about the
system's state or environment. Actuators are used to control or manipulate the system's
output or behavior.
4. Closed-Loop vs. Open-Loop: Control systems can be categorized as closed-loop
(feedback-controlled) or open-loop (no feedback). Closed-loop systems are more
common and are capable of self-correction.
5. Controller: The controller is the core component of a control system. It processes sensor
data, computes control actions, and sends signals to actuators to maintain or adjust the
system's state or behavior.
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6. Reference Signal: Control systems often receive a reference or setpoint signal that
represents the desired state or performance criteria. The controller works to minimize the
error between the reference signal and the actual state.
Types of Control Systems:
Control systems can be classified into various types based on their characteristics and
applications:
1. Proportional-Integral-Derivative (PID) Control: A common type of feedback control
system that uses three control actions (proportional, integral, and derivative) to minimize
error and maintain a desired state.
2. Industrial Control Systems (ICS): These are used in manufacturing and industrial
processes to regulate parameters such as temperature, pressure, flow, and position.
Examples include PLCs (Programmable Logic Controllers) and DCS (Distributed
Control Systems).
3. Motion Control Systems: Used in robotics and automation, these systems control the
movement of mechanical systems and robotic arms with precision.
4. Process Control Systems: Found in industries like chemical and petrochemical, these
systems manage complex chemical processes, ensuring safety and efficiency.
5. Automotive Control Systems: Control various functions in vehicles, including engine
control, transmission control, ABS (Anti-lock Braking System), and advanced driver
assistance systems (ADAS).
6. Flight Control Systems: Critical in aviation, these systems manage the control surfaces
and engines of aircraft to ensure stable flight.
7. Home Automation Systems: Control various aspects of smart homes, such as lighting,
heating, cooling, and security systems.
Advantages of Control Systems:
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Accuracy: Control systems can achieve precise control and maintain desired conditions
or outcomes.
Efficiency: They automate processes, reducing human labor and potential errors.
Safety: In applications like industrial and automotive control, safety is a paramount
concern. Control systems can help ensure safe operation.
Disadvantages of Control Systems:
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Complexity: Designing, implementing, and maintaining control systems can be complex
and require specialized knowledge.
Cost: Control systems can be expensive to develop and install, particularly in industrial
settings.
Dependency on Sensors: Control systems rely on sensors, and sensor failures can lead to
inaccuracies or system malfunctions.
Control systems are crucial in modern technology and automation, playing a significant role in
improving efficiency, safety, and precision in various industries and applications. They are
integral to the functioning of many automated and autonomous systems.
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SYSTEM DEVELOPMENT
The stages of a system life cycle
Feasibility Study
A feasibility study is a critical phase in the system development process. It assesses the viability
of a proposed project, considering various factors. Here's a detailed description:
Objectives of a Feasibility Study:
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Technical Feasibility: Evaluate whether the proposed project can be implemented using
current technology and infrastructure. Assess technical risks and limitations.
Economic Feasibility: Analyze the project's financial aspects, including development
costs, operational expenses, and potential returns on investment (ROI).
Operational Feasibility: Determine if the project aligns with the organization's business
processes and can be integrated smoothly into existing operations.
Schedule Feasibility: Assess whether the project can be completed within the desired
timeframe and if it meets any critical deadlines.
Legal and Regulatory Feasibility: Identify legal and regulatory requirements and assess
the project's compliance with them.
Market Feasibility (if applicable): Evaluate the project's potential market demand and
competitiveness.
Advantages of conducting a Feasibility Study:
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A feasibility study is conducted to make an informed decision about whether to proceed
with a project or abandon it.
It helps identify potential risks and challenges early in the project, allowing for mitigation
strategies.
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A feasibility study ensures that the project aligns with the organization's strategic goals
and financial capabilities.
It provides a clear understanding of the project's technical, operational, and economic
viability, helping stakeholders make informed investment decisions.
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2. Design stage
During the design stage, the overall structure of the system and details of the
system components are designed without being developed. The design phase is a stage
where experts define the technical details of the system. Depending on the project, these details can
include screen designs, databases, sketches, system interfaces, and prototypes. Clients use these details
to make final product design choices.There are activates that take place on this stage. They
are highlighted below:
a. Produce designs to solve a given problem – this is all about creating how the system is going
to be operating by means of Data Flow Diagram. A data flow diagram (DFD) shows how data
flows throughout a system. It is not about the order of processes; it is purely about the data flows.
To create a DFD, the expert should identify the external entities and the data flows between the
external entities and the system.
Flow chart key
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This DFD below shows the system as the hotel reservation system. It shows the
guest as an external entity. It then shows the four items of data that flow between
the guest and the booking system
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Design Input Formats
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Data capture forms: designed to collect data from users in a structured format, they
come in two types: paper-based and electronic-based. Paper-based data-capturing forms
need to be carefully designed with headings, concise instructions, character and
information fields, checkboxes, and enough writing space. Text boxes, on-screen help,
drop-down menus, radio buttons, automatic validation, and control buttons for data entry
are all features of computer-based forms.
Consider a user-friendly layout, clear instructions, and appropriate data fields
Design Output Formats
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Screen layouts: how information is presented to users on a screen
Report layouts: how information is organized in a printed or digital report
Consider readability, visual appeal, and efficient use of space
Design Validation routines
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It is a method of examining data that has been submitted to a computer to determine if it meets
specific requirements. It is a routine check that the computer does as part of its programming.
1. Range check: ensures data is within a specified range of values
2. Character check: ensures data contains only allowed characters
3. Length check: ensures data is of a specified length
4. Type check: ensures data is of the correct data type
5. Format check: ensures data conforms to a specific format
6. Presence check: ensures data is present and not left blank
7. Check digit: a digit added to a number to verify its accuracy
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3. Development and Testing stage
This stage is where the design is now brought to life and tested if it operates according to the
intended purpose.
Test Data - When a system has been developed, it needs to be tested. To test the system, data
must be created that will be used for the purpose of testing.
Test data types
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Normal data: valid and expected data values within the range of acceptability, have an
expected outcome. E.g. any whole number between 1-12.
Abnormal data: invalid or unexpected data values. This can either be:
o Data outside the range of acceptability or
o Data that is the wrong data type
o In this case, examples could be…
 any value less than 1 (i.e. 0, -6, etc.)
 any value greater than 12 (i.e. 13, 15, etc.)
 letters or nun-numeric data (i.e. July, etc.)
 non-integral values (i.e. 3.5, 4.2, etc.)
Extreme data: values at the limits of acceptability (E.g. 1 or 12)
Live data - Data that has been used with the current system hence, the results are already
known.
The system must then be fully implemented after it has been thoroughly tested. We will now
think more carefully about switching to the new system. Four popular techniques are utilized to
transition from the old system to the new one. Before selecting the approach best suited for a
given application, the pros and cons of each must be carefully considered.
4 Methods of Implementation
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End of grade 11 work
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