Lesson 1.3.pdf

Lesson 1.3: The Categories of Machines and Other IT Infrastructures or Gadgets Figure 1. The five sizes of computers Supercomputers Supercomputers are high-capacity computers with thousands of processors that can execute more than several trillion calculations per second....

Lesson 1.3: The Categories of Machines and Other IT Infrastructures or Gadgets Figure 1. The five sizes of computers Supercomputers Supercomputers are high-capacity computers with thousands of processors that can execute more than several trillion calculations per second. These are the most costly and quickest computers available. Computing professionals use supercomputers for tasks requiring the processing of enormous volumes of data, such as doing census count, forecasting the weather, designing aircraft, modeling molecules, and breaking encryption codes. Lately, they have been employed for business purposes—for instance, sifting demographic marketing information—and creating film animation. Supercomputers are still the most robust computers, but a new generation may be coming that relies on nanotechnology, using molecule-size nanostructures to create tiny machines for holding data or performing tasks. Computers the size of a bottle cap could become available that works ten times faster than today’s fasters supercomputer. Eventually, nanotech could show up in every device and appliance in your life. Figure 2. NASA researchers and university partners use supercomputers to better understand the coronavirus and how it spreads. (image source: NAS Supercomputing | Twitter) Mainframe Computers The only type of computing machine available until the late 1960s, mainframes are water- or air-cooled computers that differ in size from small, to medium, to large, depending on their use. Small mainframes, also called midsize computers; they used to be called minicomputers, although today it is a seldom- used term. Mainframes are used by large organizations—such as banks, airlines, insurance companies, and colleges—for processing millions of transactions. Often users access a mainframe through a terminal, which has a display screen and a keyboard and can input and output data but cannot process data by itself. Mainframes process billions of instructions per second. Figure 3. A mainframe computer (image source: What Are Some Examples of Mainframe Computers? | Reference.com) Workstations Workstations, introduced in the early 1980s, are costly, powerful personal computers usually used for complex scientific, mathematical, and engineering calculations and computer-aided design and computer-aided manufacturing. Workstations, providing many capabilities comparable to those of midsize mainframes, are used for such tasks as designing airplane fuselages, developing prescription drugs, and creating movie special effects. Workstations have caught the public's eye mainly for their graphics capabilities, which breathe three-dimensional life into movies. The features of low-end workstations overlap those of high-end desktop microcomputers. Figure 4. A workstation computer (image source: Daniel Byrne on Pinterest) Microcomputers Microcomputers, also called personal computers (PCs), can fit next to a desk or on a desktop or be carried around. They either are stand-alone machines or are linked to a computer network, e.g., a local area network. A local area network (LAN) connects several desktop PCs and other devices, such as printers, offices, or buildings. Microcomputers are of several types: desktop PCs, notebooks (laptops), netbooks, tablets, and smartphones. Desktop PCs (Figure 5, right) are older microcomputers whose case or main housing sits on a desk, with a keyboard in front and monitor (screen) often on top. Notebook computers (Figure 5, left), also called laptop computers, are lightweight, portable computers with a built-in monitor, keyboard, hard-disk drive, CD/DVD drive, battery, and AC adapter plugged into an electrical outlet. These are similar to desktop PCs except that they comprise an integrated unit. Because of the costly components and the smaller market for laptops, these are usually quite a bit more expensive than personal computers. Netbooks are low-cost, lightweight, computers with tiny dimensions and functions designed for basic tasks, such as web searching, email, and word processing. They have little processing power and fill a technological category between notebooks and handheld devices. Figure 5. Laptops (left) are more portable devices than desktops (right) (image source: MacBook laptop vs Mac desktop: Buying guide - Macworld UK) A tablet is a mobile gadget, typically with a mobile operating system, a rechargeable battery in a single thin package, and a touchscreen display processing circuitry. Tablets resemble smartphones in some ways and can also be used to take photos, make phone calls, send messages, record videos, and perform tasks that can also be performed by a smartphone. Smartphones, on the other hand, is a mobile phone with highly advanced features—a high- resolution touchscreen display, Wi-Fi connectivity, among others. It is a cellular phone with an integrated computer and other elements not originally associated with telephones, like an operating system, web browsing capability, and the ability to run software applications. Figure 6. A tablet is bigger than a smartphone in terms of size. (image source: iMore) Microcontrollers Microcontrollers, also called embedded computers, are the minute, specialized microprocessors installed in “smart” appliances and automobiles. These microcontrollers enable microwave ovens, for example, to store data about how long to cook your potatoes and at what power setting. Developing a new universe of experimental electronic appliances uses microcontrollers. For example, they are behind single-function products such as digital cameras, MP3, and MP4 players, which develop into hybrid forms such as gadgets that store photos, videos, and music. They also help run tiny web servers embedded in clothing, jewelry, and household appliances such as refrigerators. Also, blood-pressure monitors, airbag sensors, gas and chemical sensors for water and air, and vibrations sensors use microcontrollers. Figure 7. A microcontroller (image source: Whitehat - Posts | Facebook) Other IT Infrastructures or Gadgets A network server is a central computer that stores the collections of data (databases) and programs for connecting or supplying services to PCs, workstations, and other devices, which are called clients. A wired or wireless network links these clients. The entire system is called a client/server network. In small organizations, servers can store files, provide printing stations, and transmit emails. In large organizations, servers may also house enormous libraries of financial, sales, and product information. A computer peripheral is any detachable device that provides input and output for the computer machine. Computer peripherals, or peripheral devices, are often called “I/O devices” because they supply input and output. Some peripherals, like external hard drives, provide both input and output for the computer. A hard disk drive, also abbreviated to HDD, is an electronic data memory device that uses magnetic storage to keep and retrieve digital information using one or more rigid, rapidly rotating disks coated with magnetic material. The platters paired with magnetic heads usually arranged on a moving actuator arm, which read and write data to the platter surfaces. Data is read in a random- access manner, indicating that individual blocks of data can be stored or retrieved. A hard drive saves all your digital content. Your documents, pictures, music, videos, programs, application preferences, and operating systems represent digital content stored on a hard drive. Hard drives can be external or internal. Figure 8. Some examples of peripheral devices (image source: Design Elements - Computer Peripheral Devices | ConceptDraw on Pinterest) A solid-state drive (SSD) is a solid-state storage device that uses integrated circuit assemblies as memory to store data persistently, typically using flash memory. Sometimes called a solid-state device or a solid-state disk, although SSDs lack the physical spinning disks and movable read-write heads used by HDDs. In its purest form, an SSD is a flash memory and has no moving parts. SSD storage is much faster than its HDD equivalent. Flash drives are solid-state devices that connect to the computer via the USB port. It provides a quick and reliable method of storing data externally. It is typically removable, rewritable, and much smaller than an optical disc. An automatic voltage regulator (AVR) is a hardware device used to maintain a constant voltage and power line conditioning to the equipment load under a wide variety of conditions, even when the utility input voltage, frequency, or system load vary widely. An uninterruptible power supply (UPS) is a device that supplies battery backup when the electrical power fails to an unacceptable voltage level. Small UPS devices provide power for a few minutes, sufficient to power down the computer in an orderly manner, while larger systems have an adequate battery for several hours.