Case
Sub
Base
Root
Scanner
OCR
Barcode reader
OMR
Circuits
Wires
Registers
Buses
Processor
Operating system
Memory
Utility program
random
sequential
zig zag
none
CU
MU
CPU
ALU
Capture
Convert
Connect
None
Auxiliary
Permanent
Secondary
Primary
Pen based system
Scanning devices
Imaging systems
Barcode readers
Access
Response
Read
Write