Systems Analysis and Design: Core Concepts
Systems Analysis and Design:Core Concepts
The major goal of systems analysis and design is to improve organizational systems. Often this process involves developing or acquiring application software and training employees to use it. Application software, also called a system,is designed to support a specific organizational function or process, such as inventory management, payroll, or market analysis. The goal of application software is to turn data into information. For example, software developed for the inventory department at a bookstore may keep track of the number of books in stock of the latest best seller. Software for the payroll department may keep track of the changing pay rates of employees. A variety of off-the-shelf application software can be purchased, including WordPerfect, Excel, and PowerPoint. However, off-the-shelf software may not fit the needs of a particular organization, and so the organization must develop its own product.
In addition to application software, the information system includes:
The hardware and systems software on which the application software runs. Note that the systems software helps the computer function, whereas the application software helps the user perform tasks such as writing a paper, preparing a spreadsheet, and linking to the Internet.
Documentation and training materials, which are materials created by the systems analyst to help employees use the software they’ve helped create.
The specific job roles associated with the overall system, such as the people who run the computers and keep the software operating.
Controls, which are parts of the software written to help prevent fraud and theft.
The people who use the software in order to do their jobs.
|Topics You May Be Interested In|
|System Programs And Calls||Virtual Machines|
|Instruction Execution||File System Mounting|
|Paging In Operating System||System Model|
|File Sharing||Computer Security Classifications|
The components of a computer-based information system application are summarized in Figure 1-2. We address all the dimensions of the overall system,
with particular emphasis on application software development—your primary responsibility as a systems analyst.
Our goal is to help you understand and follow the software engineering process that leads to the creation of information systems. As shown in Figure 1-3, proven methodologies, techniques, and tools are central to software engineering processes.
Methodologies are a sequence of step-by-step approaches that help develop your final product: the information system. Most methodologies incorporate several development techniques, such as direct observations and interviews with users of the current system.
Techniques are processes that you, as an analyst, will follow to help ensure that your work is well thought-out, complete, and comprehensible to others on your project team. Techniques provide support for a wide range of tasks, including conducting thorough interviews with current and future users of the information system to determine what your system should do, planning and managing the activities in a systems development project, diagramming how the system will function, and designing the reports, such as invoices, your system will generate for its users to perform their jobs.
Tools are computer programs, such as computer-aided software engineering (CASE) tools, that make it easy to use specific techniques. These three elements— methodologies, techniques, and tools—work together to form an organizational approach to systems analysis and design.
FIGURE 1-3 The software engineering process uses proven methodologies, techniques, and tools.
In the rest of this chapter, you will learn about approaches to systems development—the data- and process-oriented approaches. You will also identify the various people who develop systems and the different types of systems they develop. The chapter ends with a discussion of some of the methodologies, techniques, and tools created to support the systems development process. Before we talk more about computer-based information systems, let’s briefly discuss what we mean by the word system.
|Topics You May Be Interested In|
|Microkernel Architecture Of Operating System||File System-recovery|
|System Boot||I/o Performance|
|System Calls||Example: The Intel Pentium|
|Segmentation||Multimedia- Network Management|
|Allocation Of Frames||Access Matrix|
Frequently Asked Questions
- Operating System Concepts ( Multi tasking, multi programming, multi-user, Multi-threading )
- Different Types of Operating Systems
- Batch Operating Systems
- Time sharing operating systems
- Distributed Operating Systems
- Network Operating System
- Real Time operating System
- Various Operating system services
- Architectures of Operating System
- Monolithic architecture - operating system
- Layered Architecture of Operating System
- Microkernel Architecture of operating system
- Hybrid Architecture of Operating System
- System Programs and Calls
- Process Management - Process concept