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Sign up with a vendor and receive access to software and applications that allow you to upload your data to that company’s server4.8 Future developments in processing and storageDescription of processing technologyoNanotechnology Tiny machines work at a molecular level to make Nano circuitsoOptical computingUsers lasers and light, not electricityoDNA computingUses strands of synthetic DNA to store dataoQuantum computing
Based on quantum mechanics and stores information using particle statesoBetter batteriesWireless charging of batteries, longer-lasting batteriesFuture development in secondary storage oHigher density disksPerpendicular recording technology: stacking magnetic bits vertically on the surface of a platter (instead of horizontally, us usual)oMolecular electrics—storage at the subatomic level 5.0 Hardware: input and outputInput hardwareDevices that translate data into a form the computer can process Translates words, numbers, sounds, and pictures into binary 0s and 1sOutput hardwareDevices that translate information processed by the computer into a form humans can understand Translates binary code into words, numbers, sounds, and pictures UNIT 5A: Input HardwareThe three major types of input hardware are keyboards, pointing devices, and source data-entry devices.5.1 KeyboardsKeyboards: convert letters, numbers, and characters into electrical signalsoEnglish keyboards differ from foreign language keyboardsHow keyboards work:oYou press a keyoThis interrupts the current flowing through the circuitsoProcessor determines where the break occursoIt compares the location of the break with the (x,y) character map for the language on the keyboard’s ROM chipoA character is stored in keyboard memory oThe character is then sent to PC and a data stream via wire or wirelessconnectionoOS interprets its own operating-system-specific commands and sends the others to the application for interpretation oMost keyboards are QWERTY-named for the first six letters on the top left of the keyboardoKeyboards are either tactile (physical) or touch screen (virtual)Keyboard typeso104-108 keys desktop standardo80-85 keys for laptopsoWired
Connect to CPU via a serial or USB portoWireless use eitherIR (infrared) technologyRadio frequency (RF) technologyTerminal typesoDumb terminalsAka video display terminal (VDT)Has display screen and keyboard Can do input and output only—no data processing oIntelligent terminalsHas screen, processor, keyboard, and memory Can perform some independent functionsAutomated teller machine; point of sale terminal; mobile data terminal5.2 Pointing deviceInclude mouse and its variants, touch screen, and various forms of pen input Pointing devices: control the position of the cursor or pointer on the screen and allow the user to select options displayed on the screen oMouse: principal pointing device oTrackball: a movable ball mounted on top of a stationary deviceoTouchpad