Studied by 5 people
Terminology
Hardware, software, peripherals, network, human resources
Hardware
Any physical parts to a computer EG: CPU Keyboard Mouse
Software
Programs/instructions that control the computer Non-physical EG: Databases Web Browsers Communication platforms
Peripherals
An outside device that allow the computer to interact with the environment or exchange info Connected EXTERNALLY Used to expand the host’s capabilities EG: Input Peripherals Scanner Microphone EG: Output Peripherals Screen Speakers
Network
Group of computers connected together to share resources Can interconnect with other networks to form larger networks
Human resources
The people operating the computers EG: The people who are responsible at maintaining employee data, promotions or hiring
Roles of a Computer
Client, Server, DNS Server, Firewall, Router
Client
Computer accessing resources that are hosted from another computer Resources may include: Documents Printers Scanners
Types of Clients
Fat, thin, hybrid
Fat clients
Performs the bulk of the processing Doesn’t necessarily rely on the server
Thin clients
Relies on the resources from the server
Hybrid clients
A mix of both fat and thin clients
Server
A computer hosting resources to be shared in the network for clients to access Combination of both hardware and software The computer provides services for other users to access EG: Google Wikipedia
DNS Server
Special type of server Maps web addresses to IP addresses IP Address: Internet Protocol, identifies a device/network on the internet Allows for the user to access any website without having to look for the IP address
Firewall
Computer/software package Any message passed through the internet passes through a firewall Monitors/protects network traffic of a computer Decides which computers get access to the network based on a set of rules Basically like a security service
Router
A routing network that passes information between two or more networks Uses a different medium for information transfer Also forwards data to the intended IP addressEG: Phone Cables
Relevant Stakeholders in developing a new system
Systems analyst, end users, software manufacturer, client company
Systems analyst
Collects information on present systems in order to examine the problems of it Uses that information to develop a more efficient system Designs the new system Tests the system for any arising issues Evaluates the system to see if it matches expectations
End users
The clients of the service The actual users of the system
Software manufacturer
Builds/develops the systems in order to be sold
Client Company
Employer organization
Methods for researching
Questionnaires, observations, interviews, documentation
Pros of Questionnaires
Answered quickly/honestly Cheap Analysed automatically
Cons of Questionnaires
People don’t often complete/return it Unclear questions cannot be explained Difficult to ask specific questions
Pros of Observation
Systems analyst can easily see advantages/disadvantages of current system Not expensive
Cons of observation
Person being watched may feel uncomfortable and work differently than usual
Pros of interviews
Questions can be explained Questions can be changed A full set of data can be recorded
Cons of interviews
Takes more time/money Answers aren’t always honest
Pros of Documentation
Saves time Can see existing inputs/outputs Allows for prediction of the size for the new system
Cons of Documentation
Very time consuming/expensive Time could be wasted if info isn’t relevant to existing system
Appropriate techniques for gathering information to arrive at a workable solution
Search, review current systems, analyze products, consult other people
Search
Identify, collect, and organize various sources to find information E.g. search engines, databases, libraries, news articles
Review current systems
Analyze current systems for effective features, functions, and other elements E.g. system documentation
Analyze Products
Analyze system/products that have been developed for the same purpose and end-users E.g. look for vulnerabilities, limitations, successful characteristics, breakthroughs, benefits, and design features
Consult other people
Identify all critical organizational capabilities that are essential to support effective planning and development E.g. interviews
Representations to illustrate system requirements
System flow chart, data flow diagram, and structure chart
System flow chart
Diagrams representing how different parts of the system are linked together and how the system should work in general
Data flow diagram
Diagrams representing how information is moving through the system together with identifying all relevant inputs and outputs to the system
Structure charts
Diagram representing the organization of a system, usually with showing the different parts in hierarchical order
Prototype
the process of building a model of a system, used to help system designers build an information system that is intuitive and easy to manipulate for end-users. A process that is involved with analysis phase of the systems development life cycle
Purpose of Prototypes
Reduced development time, reduces development costs, requires user involvement, developers receive user feedback, facilitates system implementation since users understand what to expect, results in higher user satisfaction
Steps of software life cycle
Inquiry and analysis Developing ideas Creating the solution Evaluation
Iterations
the repetition of a set of instructions for a specific number of times or until the operations yield a desired results
Importance of iterations
plenty of opportunity for user feedback, more likely to detect issues, improved usability, efficient and cost effective adaptability to project/client/team
Consequences of failing to involve the end-user in the design process
solve a different issue(s), address issues outside of the project’s scope, not addressing criteria issued by stakeholders, waste resources (time and money), be incompatible with end-user systems (app made for windows, but the computers are mac), end user may not be able to interpret UI elements
Social and ethical issues associated with the introduction of new IT systems
Firing workers because computer systems can do the same job but cheaper Because of mobile phones, workers can be reached even out of work Less social interaction due to home offices
Terms for usability
Learnability Efficiency Memorability Errors Satisfaction Complexity/Simplicity Effectiveness readability/comprehensibility
Usability problems (examples)
GPS systems, tablets
Problems of usability in GPS systems
Low quality speakers Outdated street data Inefficient routing software Poor antenna
Problems of usability in tablets
Accidental touches Poor scaling Small button size Difficult to learn features of different brands
Methods to improve the accessibility of systems
Visual impairment (Braille input devices), speakers (text to speech), Hearing and speech impairment (Subtitles), Cognitive problems & learning disabilities (Special software to provide sensory stimulation they need), Mobility impairment (Specialty keyboards/mice), Special replacements for common input items
Problems that come with Learnability
Very complicated and poor instructions
Problems that come with Efficiency
Very inefficient in processes and input
Problems that come with Memorability
Hard to remember
Problems that come with Errors
Having many errors that interfere with what the system is meant to do
Problems that come with satisfaction
Poor quality
Problems that come with Complexity/simplicity
So simple its useless, so complex it is hard to use
Problems that come with effectiveness
Doesn’t do its job
Problems that come with readability/comprehensibility
Not understandable
Moral/Ethical implications of interaction with humans and machines
AI and rights
Social implications of interaction with humans and machines
AI tricking humans with false info
Economic implications of interaction with humans and machines
Losing jobs for more efficiency
Environmental implications of interaction with humans and machines
Damaging environment, ways to make up with machines
Note
Flashcard