A1 Digital Devices

multi functional devices

  • perform several different purposes
  • they are also known as all in one devices
  • Examples: printer/ scanner
    ✅ take up less space than multiple devices, more storage space
    ❌ if one device fails all the other features could also fail since they are dependant on each other.

personal devices (PCs)

Processing speed:

multi-purpose microcomputer whose size, capabilities and price make it feasible for individual use.

  • PCs include desktops and laptops
  • Components of a computer: motherboard, CPUs, RAM, Hard disk drives, solid state drives, power supply units
  • used in workplaces for tasks like word processing, desktop publishing etc.

Random access memory (RAM)

  • essentially a device's short term memory
  • its volatile,
  • it temporarily stores everything currently running on a device
  • as soon as power is switched off, all the data is lost from the RAM
  • prevents CPU from digging through the device's slower secondary storage like HHD or SSD, every time you request a new browser or tab.
    ✅ faster memory improves overall speed in certain games and applications

storage capacity

  • refers to how much disk space one or more storage devices provided
  • measures how much data a computer system may contain

mainframes and supercomputers

supercomputers:

  • great speed and memory,
  • often dedicated a single arithmetic problem that needs processing very fast
  • used for scientific experiments, weather forecasting, code breaking, engineering simulations.

mainfarmes:

  • perform large scale transaction processing
    • manages terabytes of information in databases
    • handle large bandwidth communications
    • used by banks and large retailers to handle large scale transactions .

mobile devices

  • any digital device which can be carried around easily. teh size and weight allows them to be carried in one hand and manipulated with the other.
  • smartphones are basically a PC with the same internal components.

system on chip: a micro chip with all the neccesary electronic circuits and parts for a given system such as mobile device, on a single integrated circuit.

entertainment systems

  • computing devices taht are designed to enertain such as watching tv, listening to music, playing video games etc
  • have good hard disk storage for storing files, music, games etc.
  • have commonly in-built internet connectivity capabilities
  • digital media allows poepel to stream digital media such as films from over a network

navigation systems

  • GPS used to provide a real time map of our current location including route planing tool to give directions for chosen destination.
  • include features such as identifying traffic, roadworks and accidents that may delay journey
  • can provide accurate destination time
  • cart satnavs are often a standalone device eg TomTom but these have now been replaced with smartphones since people can access them on their phones.

servers

  • manages access to different resources and services over a network
  • other devices like PCs connect to server through ethernet cables or wifi.
  • commonly have a large storage capacity, high processing power and large amounts of memory
  • examples include web servers, mail servers, file server and print servers,

digital cameras

  • takes photos and videos and recording it as digital data.
  • does this by using a grid of photo sensors that convert light into digital pixels that computer can store usually on memory card. Megapixels (million pixels) refers to the number of individual pixels of colour that are used to record images.
  • the more the megapixels the better the quality. 20 megapixels is common in digital cameras
  • most digital cameras contain in built memory card slots to store digital pictures directly on device.
  • memory card removable allowing you to transfer pics and images onto another device such as laptop, enables to send pics through emails, access them on other devices and use programs to edit them.

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  • clock speed is mneasured in GHz.
    • CPU repeatedly reads or fetches instructions from memory and executes them

data capture and collection systems

  • imput and store data through methods other than direct data entry (eg. typing on a keyboard)
  • allows data to be entered into system directly through data capture stage and reduces number of human error issues that may happen when entering manually.
  • examples of these maybe bar code scanners, optical mark readers, magnetic ink character readers etc.
  • often used at shopping tills in supermarkets
  • bar code scans the width of dark and light bars to find the information of products on a database.
  • optical mark reader can be used to input lottery tickets since the OMR can detect what numbers from the marked location on the form.
  • MICR can used to check if cheques are legitimate. The special magnetic ink is used to write codes on bottom of cheques and read the characters to ensure the cheque is legit.

communication devices

  • devices used to move data between two devices. This can be done through wired connections or wireless
  • examples of this include network interface cards: allows data to be transferred to and from a networked computer by connecting to an ethernet cable. Commonly used with desktop personal computers.