CHAPTER 8 : DIGITAL STORAGE

STORAGE - physical material on which a computer keeps data, information, programs, and applications	v  Cloud storage - an Internet service that provides storage to computer or mobile device users. v  Capacity is the number of bytes a storage medium can hold. v  Items on a storage medium remain intact even when you turn off a computer or mobile device. v  Access time measures : -The amount of time it takes a storage device to locate an item on a storage medium. -The time required to deliver an item from memory to the processor.
HARD DISKS - contains one or more inflexible, circular platters that use magnetic particles to store data, instructions, and information	ü  Characteristics of a hard disk include : ü  An external hard disk is a separate freestanding storage device that connects with a cable to a USB port or other port on a computer or mobile device.
FLASH MEMORY STORAGE - a type of solid state media and contain no moving parts	v  A memory card is a removable flash memory device that you insert and remove from a slot in computer or mobile device. v  USB flash drives plug into a USB port on a computer or mobile device.
OPTICAL DISCS - consists of a flat, round, portable disc made of metal, plastic, and lacquer that is written and read by a laser	v  Optical discs commonly store items in a single track that spirals from the center of the disc to the edge of the disc. v  Track is divided into evenly sized sectors. v  CD-ROM - can read from but not writable or erasable. v  CD-R - users can write once, but not erase. v  CD-RW - erasable multisession disc
OTHER TYPES OF STORAGE	v  A magnetic stripe card contains a magnetic stripe that stores information. v  A smart card stores data on an integrated circuit embedded in the card. v  Radio Frequency Identification (RFID) - RFID tag consists of an antenna and a memory chip that contains the information to be transmitted via radio waves. v  Microfilm and microfiche store microscopic images of documents on a roll or sheet film.

SUMMARY

•       Variety of storage options

•       Storage capacity and storage access times

•       Advantages and various uses of cloud storage

CHAPTER 7 : INPUT AND OUTPUT

INPUT
•       Input is any data and instructions entered into the memory of a computer. •       Commonly used input methods : ü  Keyboard, Pointing Devices, Touch Screens, Pen Input, Motion Input, Voice Input, Video Input, Scanners and Reading Devices
Keyboard	-Input device that contains keys users press to enter data and instructions into a computer or mobile device. -An ergonomic keyboard has a design that reduces the chance of repetitive strain injuries.
Pointing Devices	-A small symbol on the screen whose location and shape change as a user moves a pointing device. -A mouse is a pointing device that fits under the palm of your hand comfortably. (EX : Optical mouse, Laser mouse) -A touchpad is a small, flat, rectangular pointing device that is sensitive to pressure and motion.
Pen Input	-Touch a stylus or digital pen on a flat surface to write, draw, or make selections. -A graphics tablet, also called a digitizer, is an electronic plastic board that detects and converts movements of a style or digital pen into signals that are sent to the computer.
Motion Input	-Called as gesture recognition, users can guide on-screen elements using air gestures.
Voice Input	-Process of entering input by speaking into a microphone. -Voice recognition, also called speech recognition, is the computer or mobile device’s capability of distinguishing spoken words.
Audio Input	-Process of entering any sound into the computer such as speech, music, and sound effects. -Music production software allows users to record, compose, mix, and edit music and sounds.
Video Input	-Process of capturing full-motion images and storing them on a computer or mobile device’s storage medium.
Scanners and Reading Devices	-Light-sensing input device that reads printed text and graphics and then translates the results into a form the computer can process. (EX: Optical reader, Bar code reader, QR Code, Magstripe Readers)
OUTPUT
·       Output is data that has been processed into a useful form.
Displays	-A display visually conveys text, graphics, and video information -A monitor is a display that is packaged as a separate peripheral device.
Printers	-A printer produces text and graphics on a physical medium -A nonimpact printer forms characters and graphics on a piece of paper without actually contacting the paper. -An ink-jet printer forms characters and graphics by spraying tiny drops of liquid ink onto a piece of paper -Laser printing has a high speed and high quality. -All-in-one printer is a single device that prints, scans, copies, and faxes. -Thermal printer generates images by pushing electrically heated pins against the heat-sensitive paper. -Mobile printer is a small, lightweight, battery-powered printer that allows a mobile user to print from a mobile device. -Label printer is a small printer that prints on an adhesive-type material that can be placed on a variety of items. -Impact printers form characters and graphics on a piece of paper by striking a mechanism against an inked ribbon that physically contacts the paper.
Other Output Devices	Sound Speakers -> To their computers, game consoles, and mobile devices to generate higher-quality sounds. Headphones -> Speakers that cover or placed outside of the ear. Earbuds/Earphones -> rest inside the ear canal. Data Projector -> Device that takes the text and images displaying on a computer or mobile device screen and projects them on a larger screen. Joysticks -> Output devices when include force feedback.
Assistive Technology Input and Output	Braille input, Braille printer

SUMMARY

v  Variety of options for input and output

v  Several assistive technology options for input and output