Lesson 1

Information System

• a set of interrelated components that collect, process, store and provide as output the information needed to complete business tasks.
• consists of software, database, and manual processes

Systems analysis

• Activities that help to understand and specify what the new system should accomplish
• System analysis describes in detail what a system must do to satisfy the need or solve the problem.

Systems design

• Activities that enable a person to describe in detail how the information system will be implemented to provide the needed solution
• Describe how the system will work
• Specifies in deetail all the components of the solution system and how they work together

System analysis vs design

• SA : what is required for the new system to solve the problem
• SD : how the system will operate to solve the problem

System Analyst

• Plan, capture the vision, understanding details specifying needs - before designing and writing code that satisfies the vision

System analysis and design

• provides the tools and technques required to complete the IS development process:

1. Understand the need (business need)
2. Capture the vision
3. Define a solution
4. Communicate the vision and the solution
5. Build the solution or direct others in building the solution
6. Confirm that the solution meets the need
7. Launch the solution application

System Development Life Cycle *

• framework taht identifies all the activities required to research, build, deploy, and often maintain an information system
• includes all activities needed for planning, system analysis, system design, programming, testing and user training stages of information systems developement

6 core processes *

1. Identify the problem and obtain approval
2. Plan and monitor the project
3. Discover and understand details
4. Design system components
5. Build, test and integrate system components
6. Complete system tests and deploy the solution

IS development methodology

• set of comprehensive guidelines for carrying out all the activities of each core proces of the SDLC
• each methodology prescribes a way of carrying out the development project
• every organization develops its own system development methodology over time to suit its needs

Agile Development

• most common methodology to implement SDLC
• to improve chance of project success

Agile Development philosophy

• neither team members nor the users completely understand the problems and complexities of a new system
• the project plan and the execution of the project must be responsive to unanticipated issues
• the plan must be agile and flexible
• it must have procedures in place to allow for, anticipate, and even embrace changes and new requirements that come up during the development process.

Iterative Development

• An approach to system development in which the system is grown in an almost organic fashion
• core components are deveoped first and then additional components are added
• iterative: the six core develoment processes are repeated for each components

1. by dividing system into subsystems, most difficult problems can be identified and addressed early
2. many of today's systems are large and complex taht it is impossible to remember and understand everything
3. by focusing on a subsystem at a time, requirements are fewer and easier to solve
4. developing a system makes the entire development process more flexible and able to address new requirements and issues tha come up throughout the project

• key element of ID is dividing system components into pieces that can be completed in two to four weeks
• during one iteration, all the coure development processes are involved
• the result is working part of the system, even though it may only have a portion of the functionality that is ultimately required.
• developers choose components for each iteration based on priority, either the components most needed or riskies to implement