Foundational Topic 1 – Notes

Information Systems Hardware

I. Foundational Topics in IS Hardware

A. Input Technologies – keyboards, scanners, graphic tablets, etc.

1. Entering Text and Numbers – Keyboards – QWERTY (other combination available today), Ergonomic, Wireless (RF or Bluetoth), Virtual Laser Keyboard (keyboard projected onto a surface by a laser

2. Selecting and Pointing – Mouse, Mouse Pen, Light Pen, Graphics Tablet, Eye-tracking device

3. Entering Batch Data – lots of data being entered at a single input, Scanners, OCR (Optical Character Recognition), MICR (Magnetic Ink Character Recognition, as in some checks), RFID (Radio Frequency Identification)

a. Other Scanning technologies – Smart Cards (credit card sized with microprocessor chips or memory circuits and/or magnetic strips), Biometric devices (fingerprint or retinal scanners, hand/face geometry)

4. Entering Audio and Video – must be digitized before it can be maniupulated/stored/displayed/played

a. Voice Input – Speech Recognition/Voice-to-Text Software, Interactive Voice Response

b. Other Forms of Audio Input – use and manipulate sounds from a variety of sources

c. Video Input – digital cameras and digital video, Streaming Video from Webcams, Streaming Media – streaming video and sound

B. Processing: Transforming Inputs into Outputs – once we have the data, it must be processed by the computer

1. Binary Codes – Base 2 – all 0’s and 1’s

a. Bit = Binary Digit, a 0 or a 1

b. Byte represents a character and is (usually) 8 bits – 00000000 to 11111111 (Base 2) can represent 0 to 255 (Base 10), totaling 256

c. ASCII – a type of coding system where each byte has a particular meaning (A or a or 2 or # or +); another systems is EBCDIC (from IBM)

2. System Unit – box that houses all the components

3. Motherboard – plastic/fiberglass board unit that holds all the basic processing components; Power Supply – converts electricity from wall socket to lower voltage

4. Clock Speed – how fast the computer runs

Not in text: Central Processing Unit (CPU) – the chip itself; consists of Arithmetic-Logic Unit (ALU – does calculations and comparisons) and Control Unit (sends data to/from various parts of the computer and sequences events in the chip)

5. Storage – different types of storage for different purposes, mostly differing in capacity, volatility, and read/write speed

6. Primary Storage – the main memory used when running the computer – RAM and ROM

a. Random Access Memory (RAM) – primary memory, volatile (goes away when power is shut off: save, Save, SAVE!!!)

b. Read-Only Memory (ROM) – does NOT go away when power is shut off, used to boot the PC, Flash memory/EEPROM

c. Cache Memory – small, very fast memory used by the processor (not as fast as a register, but there is more of it); Internal (Level 1 or L1), External (Secondary Cache or Level 2 or L2)

7. Secondary Storage –non-volatile, keeps data after computer is turned off; hard drives, diskette drives, flash (jump) drives, tape

a. Hard Drives – usually the main storage device, first hard drive is denoted as C: - Read/Write Heads, Arms, Platters, Tracks, Sectors, Cylinders; Seek Time, Rotational Delay, Transfer Time

8. Removable Storage – Flash (Jump) drives, Diskette Drives and Diskettes – 3-1/2”, 5-1/4”, 8”, 12”

a. Optical Disk Storage – uses laser technology; more storage than disks

1. Compact Discs (CDs) – CD-ROM, CD-R, CD-RW

2. Digital Versatile Disks (DVDs) – DVD-ROM, DVD-R, DVD-RW – holds more than a CD, used for video

b. Magnetic Tapes – old, but cheap and high density; used for backup

9. Ports – interfaces for other devices to connect to the PC

C. Output Technologies

1. Video Output – Monitors – Cathode Ray Tube (CRT), Liquid Crystal Display (LCD), Organic Light-Emitting Diodes (OLED), Electronic Paper (microscopic beads on paper that change color in response to electrical charges)

2. Printers and Plotters – Dot Matrix, Ink-jet, Laser

3. Audio Output – Speakers and Sound Cards