Peripherals: Input, Output, Storage, Accessibility, and Data Processing
- Devices that provide data to the computer.
- Examples: camera, webcam, scanner, microphone, graphics tablet, MIDI keyboard, trackball, game controller, mouse, keyboard.
Output Devices
- Devices that output information to the user.
- Examples: printer, projector, monitor, headphones, speakers, haptic feedback game controller, braille simulator.
- Devices that function as both input and output.
- Examples: touch screens, whiteboards.
Storage Devices
- Key characteristics:
- Capacity: Measured in gigabytes, megabytes, or terabytes.
- Speed: Data transfer rate.
- Cost.
- Durability.
- Reliability.
- Portability.
Types of Storage Devices
Magnetic Hard Disk Drives (HDDs)
- Features a read/write head and one or more platters.
- Advantages: Very large capacities.
- Disadvantages: Less portable, susceptible to damage due to moving parts and potential head crashes.
Solid State Disks (SSDs)
- Use memory chips and have no moving parts.
- Advantages: Faster, more durable, more reliable, and more portable than HDDs.
- Disadvantages: More expensive per gigabyte than HDDs.
- Includes memory cards (micro SD), USB removable storage (memory sticks), and internal storage in phones and tablets.
- Cameras require certain specs of SD cards to write data quickly enough.
- Examples: Blu-ray, DVD, CD-ROM. Data is read by a laser following spiral tracks.
- Capacities: CDs (700MB), DVDs (5GB), Blu-rays (25-50GB).
- Advantages: Removable, cheap to produce.
- Disadvantages: Fragile, can be scratched, susceptible to organic damage, not ideal for archiving.
- Track length (if uncoiled): CD (5 km), Blu-ray (27 km).
Magnetic Tape
- Sequential access, suitable for backup.
- Advantages: Cheap, reliable, portable.
- Disadvantages: can only be accessed from one end to the other.
Accessibility Devices
- Devices that allow technology to be used by people with disabilities.
- Examples: ergonomic keyboards, speech recognition software, Braille printers, text-to-speech software, screen magnifiers, customizable mouse cursors, narrator, color filters.
Data Processing
Manual Data Processing
- Data is entered manually.
- Disadvantages: Tedious, slow, error-prone.
Automated Data Processing
- Computers take over the data processing role.
- Examples: ANPR, smart meters, earthquake recording, race timing, weather stations.
- Advantages: Removes human error.