Sign up with a vendor and receive access to software and applications that

Sign up with a vendor and receive access to software

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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 server 4.8 Future developments in processing and storage Description of processing technology o Nanotechnology Tiny machines work at a molecular level to make Nano circuits o Optical computing Users lasers and light, not electricity o DNA computing Uses strands of synthetic DNA to store data o Quantum computing
Based on quantum mechanics and stores information using particle states o Better batteries Wireless charging of batteries, longer-lasting batteries Future development in secondary storage o Higher density disks Perpendicular recording technology: stacking magnetic bits vertically on the surface of a platter (instead of horizontally, us usual) o Molecular electrics—storage at the subatomic level 5.0 Hardware: input and output Input hardware Devices that translate data into a form the computer can process Translates words, numbers, sounds, and pictures into binary 0s and 1s Output hardware Devices 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 Hardware The three major types of input hardware are keyboards, pointing devices , and source data-entry devices . 5.1 Keyboards Keyboards : convert letters, numbers, and characters into electrical signals o English keyboards differ from foreign language keyboards How keyboards work: o You press a key o This interrupts the current flowing through the circuits o Processor determines where the break occurs o It compares the location of the break with the (x,y) character map for the language on the keyboard’s ROM chip o A character is stored in keyboard memory o The character is then sent to PC and a data stream via wire or wireless connection o OS interprets its own operating-system-specific commands and sends the others to the application for interpretation o Most keyboards are QWERTY-named for the first six letters on the top left of the keyboard o Keyboards are either tactile (physical) or touch screen (virtual) Keyboard types o 104-108 keys desktop standard o 80-85 keys for laptops o Wired
Connect to CPU via a serial or USB port o Wireless use either IR (infrared) technology Radio frequency (RF) technology Terminal types o Dumb terminals Aka video display terminal (VDT) Has display screen and keyboard Can do input and output only—no data processing o Intelligent terminals Has screen, processor, keyboard, and memory Can perform some independent functions Automated teller machine; point of sale terminal; mobile data terminal 5.2 Pointing device Include 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 o Mouse : principal pointing device o Trackball : a movable ball mounted on top of a stationary device o Touchpad

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