Digital Methods of Exchanging Data

Digital Methods of Exchanging Data

1. User Interface

   • Types of User Interfaces
     • Graphical User Interface (GUI)
       • A graphics-based operating system interface which uses icons, menus and a mouse. The user navigates the system through clicks and/or pull down menus.
     • Command Line Interface (CLI)
       • A computer program that runs on text-based inputs to execute a variety of tasks. Instead of pointing and clicking with a mouse (as seen in a GUI), single-line commands are received which then interact with system elements like file management.
     • Menu-driven User Interface
       • An interface consisting of a series of screens which are navigated through choosing options from lists.
     • Touch User Interface
       • A computer-pointing technology based upon the sense of touch (also known as haptics). Unlike a GUI (which relies on the sense of sight), a TUI enables not only a sense of touch to innervate and activates computer-based functions, it also allows users with visual impairments to have an added level of interaction (based on tactile or Braille input).
     • Voice User Interface (VUI)
       • Allows users to interact with a system through the use of voice or speech commands. Examples of these VUIs include Siri, Google Assistant, and Alexa. VUIs allows a hands-free, eyes-free way in which users can interacting with a product whilst having their attention elsewhere.
     • Natural Language User Interface
       • A conversational interface. The user will type a command and the application in return will give results to the user (or ask for clarification). Examples of these include conversational commerce, bots, AI agents etc.

2. Data Structure

   • A data structure is a storage which is used to store and organise data. This is a way of arranging data on a computer so it is able to be accessed and updated with efficiency.
   • Classification of Data Structure
     • Linear Data Structure
       • In this structure, data elements are arranged sequentially or linearly (each element is attached to its previous and next adjacent elements).
       • Examples
         • Array
         • Stack
         • Queue
         • Linked List
     • Static Data Structure
       • Has a fixed memory size. It is easier to access elements in this structure.
       • Examples
         • Array
     • Dynamic Data Structure
       • Size is not fixed. It can be updated randomly during the runtime which could be considered efficient concerning the memory (space) complexity of the code.
       • Examples
         • Queue
         • Stack
     • Non-linear Data Structure
       • Data elements are not placed sequentially or linearly. Cannot traverse all the elements in a single run only.
       • Examples
         • Trees
         • Graphs
   • Keys
     • A key is always a string enclosed by quotation marks.
   • Values
     • A value can be a string, boolean, array, number or object.
   • Array
     • JSON arrays contain zero, one, or more ordered elements, which are separated by commas. The array is enclosed by square brackets [].

3. Data Specifications

   • JSON
     • JSON object
     • array
     • boolean
     • null
     • string
     • integer
     • CANNOT be
       • function
       • data
       • undefined
   • XML
     • boolean
     • integer
     • decimal
     • string
     • duration
     • dateTime
     • data
     • time

4. Data Interface

   • Data interface is how data is presented to the user.
   • Tables
     • Row
     • Column
     • Cell
     • Headings
   • Graphs
     • Pie Chart
     • Histograms
     • Bar Chart

5. REST Principles

   • REpresentational State Transfer
     • An architectural style for providing standards between the computer systems on the web. REST Principles allow it to be easier for systems to communicate with one another.
     • RESTful systems are usually characterised by how they are stateless, and separate the concerns of the server and the client.
     • Uniform Interface
       • Everything has an ID
       • Standard HTTP methods used
     • Client-server
       • Client utilises the resource ID
       • The server provides an API endpoint
     • Stateless
       • The server is not required to remember previous requests
       • Client manages its own state
     • Cacheable
       • All resources used are copies to improve on scalability
     • Layered System
       • The application supports linking of other resources