Educational institution: MCOU "Secondary School No. 4"
Brief job description:
Publication date: 2017-04-25 Test on the topic: A computer is a universal machine for working with information Mikhailovskikh Svetlana Vladimirovna A test to test the knowledge of 5th grade students on the topic "Computer - a universal machine for working with information"
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Test on the topic: A computer is a universal machine for working with information
Test topic: Computer - a universal machine for working with information
Beginning of the form
1. Select the one you need to define: “A computer is.”
universal software-controlled device for information processing.
device for performing calculations.
device for creating text documents.
2. Hard function disk:
used for information processing.
used for long-term storage of information.
used to enter information.
3. Select the one you want to define the keyboard.
information storage device.
information output device.
4. Choose the correct definition for the term "mouse"
device for fast travel on the screen and select the required information.
device for entering information by pressing keys.
5. What is a processor?
a device designed for computing, processing information and controlling the operation of a computer
6. Select the appropriate description for your computer's RAM?
device for long-term storage of information.
the information is contained in it only while the computer is running.
information presented in a form suitable for processing by a computer.
7. What is a monitor?
device for entering information by pressing keys.
device for long-term storage of information.
device for visual display of information.
8. Printer function.
printing information on paper.
visual display of information.
information processing and computer control.
Lesson 2. The computer is a universal machine for working with information .
Lesson objectives:
To help students understand the structure of a computer, the concept of basic PC configuration, and give the basic concepts necessary to start working on a computer.
Upbringing information culture students, attentiveness, accuracy, discipline, perseverance.
Development of cognitive interests, skills in working with a mouse and keyboard, self-control, and note-taking skills.
Planned educational results:
subject - knowledge of basic computer devices and their functions;
meta-subject – basics of ICT competence;
personal – an idea of the role of computers in life modern man; ability and readiness to accept values healthy image life through knowledge of the basic hygienic, ergonomic and technical conditions for the safe operation of information and communication technologies(ICT)
Equipment: teacher’s personal computer (PC), multimedia projector, screen; Students' PCs.
Electronic supplement to the textbook: 1) presentation “Computer is a universal machine for working with information.”
Lesson plan:
1. Org. moment. (2 min)
2. Updating knowledge. (7 min)
3. Theoretical part. (22 min)
4. D/z (2 min)
5. Questions from students. (5 min)
6. Lesson summary. (2 min)
Lesson progress:
1. Org. moment.
Greetings, checking those present. Explanation of the lesson.
2. Test of knowledge.
In the last lesson we started getting acquainted with the computer. Today we will look at what computer devices almost every PC has, why they are needed and some of their characteristics.
3. Theoretical part.
A computer is a universal machine for working with information. Information presented in a form suitable for storage, transmission and processing by a computer is called data.
The science of computer science deals with the study of all possible ways of transmitting, storing and processing information.
Sometimes they say “personal computer”. The clarification “personal” here is not accidental - it means your own, personal, accessible to most people, because there is large number other types of computers that cannot be called personal - workstations for enterprises, servers for connecting many computers to a network, etc. in the future, when we say “computer” we will mean a personal computer.
A personal computer is a computer designed to serve one worker. Its characteristics may differ from mainframe computers, but it is functionally capable of performing similar operations. A computer is a universal machine for working with information.Information presented in a form suitable for storage, transmission and processing by a computer is called data.
Basic PC configuration - minimum kit hardware, sufficient to start working with a computer. Currently, for desktop PCs, the basic configuration is considered to include four devices:
System unit;
Monitor;
Keyboard;
Mouse.
System unit - main unit computer system. It contains devices that are considered internal. Devices connected to the system unit from the outside are considered external.
The system unit includes a processor, RAM, hard and floppy disk drives, optical disk drives and some other devices. On the front panel you see several buttons - the already familiar Power button - turns on and the Reset button - restarts the computer, which can only be used with the permission of the teacher. Several light indicators indicate power on and access to the hard drive. Two drives - for CDs and floppy disks, which we will talk about in the next lesson.
Monitor is a device for visual reproduction of symbolic and graphic information. Serves as an output device. They vaguely resemble household televisions.
IN desktop computers Typically, cathode ray tube (CRT) monitors are used. The image on the monitor screen is created by a beam of electrons emitted by an electron gun. This beam of electrons is accelerated by high electrical voltage (tens of kilovolts) and falls on the inner surface of the screen, coated with a phosphor (a substance that glows under the influence of an electron beam).
The beam control system forces it to run across the entire screen line by line (creates a raster), and also regulates its intensity (accordingly, the brightness of the phosphor dot). The user sees the image on the monitor screen, since the phosphor emits light rays in the visible part of the spectrum. The smaller the image dot size (phosphor dot), the higher the image quality; in high-quality monitors, the dot size is 0.22 mm.
However, the monitor also emits high static electrical potential, electromagnetic radiation and x-ray radiation, which may have adverse effects on human health. Modern monitors are practically safe, as they meet strict sanitary and hygienic requirements.
Laptop and pocket computers use flat-panel liquid crystal (LCD) monitors. Recently, such monitors have become widely used in desktop computers.
LCDs (Liquid Crystal Displays) are made of a substance that is in a liquid state, but at the same time has some properties inherent in crystalline bodies. In fact, these are liquids that have anisotropy of properties (in particular, optical ones) associated with order in the orientation of molecules. Molecules of liquid crystals under the influence of electrical voltage can change their orientation and, as a result, change the properties of the light beam passing through them.
The advantage of LCD monitors over CRT monitors is the absence of electromagnetic radiation harmful to humans and their compactness. But LCD monitors also have disadvantages. The most important of them are poor color rendering and blurring of fast-moving images. In other words, if you take a high-quality CRT monitor, it will be suitable for any task without reservations - for working with text, for processing photographs, for playing games, and so on; at the same time, among LCD monitors, one can distinguish models that are suitable for games - but they are unsuitable for working with photographs; one can distinguish models that have excellent color rendition - but they are not suitable for dynamic games, and so on.
Monitors may have different screen sizes. Screen diagonal size is measured in inches (1 inch = 2.54 cm) and is usually 15, 17, 19 or more inches.
Keyboard is a keyboard device designed to control the operation of a computer and enter information into it. Information is entered in the form of alphanumeric character data. Standard keyboard has 104 keys and 3 indicator lights in the upper right corner informing about operating modes.
The mouse is a “graphical” control device.
As you move the mouse across the mousepad, the mouse pointer moves on the screen, allowing you to point at and/or select objects. Using the mouse keys (there can be two or three of them) you can specify one or another type of operation with an object. And using the wheel, you can scroll up or down images, text or web pages that do not fit entirely on the screen.
In optical-mechanical mice, the main working organ is a massive ball (metal, covered with rubber). When the mouse moves across the surface, it rotates, the rotation is transmitted to two shafts, the position of which is read by infrared optocouplers (i.e., light emitter-photodetector pairs) and then converted into an electrical signal that controls the movement of the mouse pointer on the monitor screen. The main “enemy” of such a mouse is pollution.
Currently, optical mice, which have no mechanical parts, are widely used. A light source located inside the mouse illuminates the surface, and the reflected light is captured by a photodetector and converted into cursor movement on the screen.
Modern mouse models can be wireless, i.e. connecting to a computer without a cable.
Peripherals are devices that are connected to the computer externally. Typically these devices are designed to input and output information.
Here are some of them: printer, scanner, modem, DVB card and satellite dish, Web camera.
The printer is used to output information onto paper media (paper).
There are three types of printers: dot matrix, inkjet, laser.
Dot matrix printers are impact printers. The print head of a dot matrix printer consists of a vertical column of small rods (usually 9 or 24) that are "popped" out of the head by a magnetic field and strike the paper (through the ink ribbon). As the print head moves, it leaves a string of characters on the paper.
The disadvantages of dot matrix printers are that they print slowly, produce a lot of noise, and print quality is poor (about the quality of a typewriter).
In recent years, black-and-white and color inkjet printers have become widespread. They use an ink print head that, under pressure, releases ink from a series of tiny holes onto the paper. As the print head moves along the paper, it leaves a line of characters or a strip of image.
Inkjet printers can print fairly quickly (up to several pages per minute) and produce little noise. The quality of printing (including color) is determined by the resolution of inkjet printers, which can reach photographic quality of 2400 dpi. This means that a 1-inch horizontal stripe of image is formed from 2400 dots (ink drops).
Laser printers provide virtually silent printing. High speed Laser printers achieve printing (up to 30 pages per minute) through page-by-page printing, in which the entire page is printed at once.
The high typographic quality of laser printers is ensured by high resolution, which can reach 1200 dpi or more.
Plotter. For displaying complex and wide-format graphic objects (posters, drawings, electrical and electronic circuits etc.) special output devices are used - plotters. The operating principle of a plotter is the same as an inkjet printer.
Scanners are used to automatically enter texts and graphics into a computer.
There are two types of scanners: hand-held and flatbed.
A handheld computer scanner is similar to the scanner used in supermarkets to read barcodes. Such a scanner moves along a sheet of information line by line manually, and the information is entered into a computer for further editing. A flatbed scanner looks and works much the same as a copier - the lid is lifted, text or drawing is placed on the working area, and the information is read. Flatbed scanners these days are usually all color.
Text recognition systems allow you to convert scanned text from graphic format to text.
The resolution of scanners is 600 dpi and higher.
A modem or modem card is used for communication remote computers over the telephone network. The modem can be internal (installed inside the system unit) or external (located next to the system unit and connected to it using a cable.
A DVB card and a satellite dish are used for the so-called “asynchronous” connection of a computer to the Internet. If you have a DVB card and a satellite dish, two communication channels are used to connect to the Internet: a modem is used to transmit data from the user, and a modem is used to receive data. satellite channel, the data flow rate in which is several times higher than the modem.
To organize video conferences (or just chat) on the endless Internet, a Web camera is useful. With the help of these devices (and, naturally, fast local networks), you can arrange a meeting with your employees at any time, without taking them away from their usual jobs. And this, as practice shows, provides very tangible practical benefits.
Let's make a reservation right away - we are not talking about real video cameras here. That is, you can’t even dream of good optics, high-quality color rendition and other similar luxuries. And it wouldn’t even occur to you to save a video image from a webcam. After all, this unit is needed for something completely different - to ensure that your computer receives a video stream with a quality and volume sufficient for transmission on the Internet.
There is, however, one catch here. Almost all webcams are not designed to work in the slow modem connection mode. Give it to them digital channels communications - and then these devices will show themselves in all their glory.
As for Russia, unfortunately, there is no way to ensure the transmission of such a data stream in real time. Neither at transmitting devices, nor at communication channels. Therefore, the maximum that your interlocutor can count on is the appearance of your personality in a tiny window slightly smaller than a cigarette pack (image size - up to 320x200 pixels). If this is enough for you, well, purchasing a webcam can brighten up your gray computer everyday life a little.
Since the webcam does not produce a static image, you need to take into account another important value - the frame refresh rate.
So, on a regular modem connection, even with a tiny picture of 150x200 pixels, you most likely will not get the required 24 frames (in reality, from 10 to 20). This means that jerks and delays are inevitable... However, don’t be upset – alternative ways connections to the Internet are making their way more and more persistently and, perhaps, in a year or two your counterparts will be able to enjoy decent quality images at least a quarter of the screen in size.
In the meantime, pay attention to other indicators of the webcam - reaction to different lighting conditions, the presence of a built-in or additional microphone, the length of the USB connecting cable, the camera’s ability to work in conjunction with popular programs for voice and video communication (for example, Microsoft NetMeeting). And, of course, on maximum resolution: Although image quality of 640x480 pixels has long been the standard, there are models on the market with a much lower resolution threshold (many cameras costing up to $50 provide resolution only up to 352x288 pixels).
By the way, did you know that a good webcam can successfully replace a digital camera? Most cameras can not only transmit a stream of video information to a computer, but also extract individual picture frames from this stream. But their future fate depends on the quality of the camera: expensive models can save images in the built-in memory without requiring a constant connection to a computer, while cheaper ones are forced to immediately dump all their “cargo” onto the hard drive.
Although, of course, a real digital camera works much better, and the quality is different... Moreover, many mid-price digital cameras can also work as web cameras, if necessary.
And one last thing. Almost all camera models released after 1999 connect to a computer via a USB connector and do not require an additional power source.
Questions for consolidation:
What does "personal computer" mean?
2. What is "basic PC configuration"?
3. What types of monitors do you know?
4. What is mouse resolution?
5. What is the difference between optical-mechanical and optical mice?
6. What other devices for entering information into a computer do you know?
4. Homework: Textbook: §2. (p.10)
Know what the basic configuration of a PC and computer devices are. Students who have computers at home should continue to master the “ten-finger touch typing method.”
Additional task: find information about additional devices connected to the computer.
5. Questions from students.
Answers to student questions.
6. Lesson summary.
Summing up the lesson. Grading.
During the lesson we learned what a basic PC configuration is and what devices are included in the basic PC configuration.
Presentation for the first lesson in 6th grade on teaching materials by Bosova L.L. 1. We repeat the safety rules 2. We repeat the 5th grade material in the sections: “Information”, “How a computer works”, “Computer in the service of a person” 3. We move on to studying the topic: “The computer is a universal machine for working with information " 4. Lesson summary, d/z
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Safety regulations
If you are a good boy, then don’t put your finger in the socket, don’t play with the wires: do you know if there is a heaven? Safety regulations
Know how to be thrifty, and don’t hit the keys, take this fact into account, electrical contact. Safety regulations
A mouse can become a friend if you don't offend it. Train her skillfully, do not spin her around idle. Safety regulations
If you enter “answer” and the computer says “no”, don’t knock on the display, it’s better to learn the rules! Safety regulations
If your machine malfunctions, you need patience. There are no problems, even with a smart computer! Safety regulations
If there is a spark somewhere or something is smoking, don’t waste your time - you need to call an adult. After all, we ourselves know that a flame can ignite from a spark. Safety regulations
Everyone knows the rest: So that they don’t jump up from their seats, Don’t shout, don’t push, Don’t fight over computers. Safety regulations
No one comes to us in jackets, fur coats and coats. Friends, you can’t be in the office with dirty shoes. Safety regulations
Start work strictly with the permission of the teacher, and keep in mind: you are responsible for the order in the office. Safety regulations
1 Let's remember a little material from grade 5
INFORMATION Information is information about the world around us.
from books How does a person receive information? from a teacher from the Internet from friends
Humans and animals receive information through the senses Sense organs Information Vision Hearing Taste Smell Touch Other senses
Types of information by presentation form Numerical Quantitative characteristics of the surrounding world - height, weight, age, forest area.... Text Everything that is printed or written in any of the existing languages Graphic Drawings, paintings, diagrams, drawings, maps, photographs, etc. Sound Everything we hear is human speech, music, birdsong, etc. Video information Sequences of images - films, cartoons, etc.
The science of computer science deals with the study of all possible ways of transmitting, storing and processing information. A computer helps a person store, process and transmit information.
A computer consists of devices that perform some of the functions of a thinking person: Human organs Information process Computer devices Sense organs Reception (input) of information Keyboard, mouse, scanner Brain Information storage Memory Brain Information processing Processor Organs of speech and musculoskeletal system Transmission (output) of information Monitor, printer
2 Computer hardware and software
How does a computer work?
The main thing in a computer is the system unit, which includes a processor, memory, hard and magnetic drives, power supply, etc.
The processor is designed for computing, processing information and controlling the operation of the computer
Computer memory is used to store data. There are two types of memory: RAM and permanent memory. The devices that implement them are called RAM and ROM. ROM stores instructions that determine how the computer turns on. These instructions are not deleted even when the computer is turned off. All programs and data necessary for the operation of the computer are placed in RAM. After turning off the computer, all information contained in the RAM is deleted. RAM board Read-only memory
For long-term storage of information, long-term memory is used: magnetic disks, optical discs, other devices. Magnetic disks can be hard or flexible. Hard drives large capacity built into the system unit and are permanently located there. IN system unit There are also floppy disk drives - floppy disks. Unlike floppy drives, hard drives cannot be transferred. Recently, optical disks and flash drives have become more widespread.
The following devices are used to enter information into the computer memory: keyboard scanner To output information into the computer memory the following devices are used: monitor printer
Additional devices: mouse acoustic speakers joystick others All of them make up the computer hardware Let’s perform the “Hardware” test:
26 A machine must work, a person must think. IBM principle 3 THE COMPUTER IN THE SERVICE OF HUMAN
27 Computer Typewriter Clerk Personal secretary Accountant Information desk Librarian Publisher Translator Postman Artist Animator Constructor Fashion designer Architect Designer Composer and musician Doctor Teacher Leisure organizer COMPUTER “PROFESSIONS”
Let's move on to studying new topic: § 1.1 - Who uses a computer in their professional activities? - What operations can be performed using a computer? An object that is suitable for many purposes, has a variety of purposes, and performs various functions is called universal. - Can we say that a computer is a universal machine? - What actions can a computer perform with information? - What information does the computer work with? Data refers to a variety of information presented in a form suitable for processing by a computer. Data processing is carried out on a computer using programs.
Fill out the diagram: in the appropriate blocks, indicate the name of the programs that process text, graphic, numeric and sound information on a computer.
Programs Text information Numerical information Audio information Graphic information Notepad Sound recording MS Power Point Calculator Paint MS Excel MS Word Movie Maker
Completing tasks No. 3 and No. 4 on page 4 of the workbook. Homework: § 1.1, RT: No. 1, No. 2 - p.3. Material for the curious: pp. 103-112 § 4.14-4.18 Let's summarize: p. 10 in the textbook What does the word “universal” mean? Why is a computer a universal machine for working with information? Give an example of using computers? Remember what programs are designed for processing numerical, text and graphic information?
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Target: update students’ knowledge acquired in 5th grade;
Tasks:
- restore knowledge about computer science as a science about methods of storing, processing and transmitting information;
- repeat computer hardware and software;
- restore knowledge about the computer as a universal machine for working with information;
- introduce the main stages of the history of computer technology;
- improve the skill of working with a keyboard simulator.
Basic concepts:
- information;
- data;
- informatics;
- computer.
Lesson progress
1. The computer as a universal machine for working with information.
(Presentation 1)
Computers have revolutionized our lives. They changed the way people worked, educated, traded and entertained. They are used by doctors and farmers, teachers and bank workers, engineers and designers. You cannot do without computers when preparing for the publication of books and magazines, in scientific and engineering calculations, when creating special effects in cinema and television, and in many other cases. Some professions are completely related to computers.
An object suitable for many purposes, with a variety of purposes, performing a variety of functions is called universal.
A computer is a universal machine for working with information. The word “universal” emphasizes that a computer can be used for many purposes: process, store and transmit a wide variety of information, be used in the most different types human activity.
But no matter what a person does with the help of a computer, it is always work with information.
2. Repetition of the concept of information. Types of information by method of receipt and presentation.
What is information?
How does a person perceive information?
How can the information we receive be presented?
Using a computer always means working with information - numbers, texts, sounds or images.
The most diverse information presented in a form suitable for processing by a computer is called yut data.
The computer processes data using programs installed on it. The wider the spectrum software, the greater the number of problems that can be solved on a computer.
But at the same time, do not forget the IBM principle that a machine must work, a person must think.
3. An excursion into the history of computer technology.
(Presentation 2)
Already in the Stone Age, the need for counting arose. Our distant ancestors were helped in this by their primitive “computer” - ten fingers on their hands.
In Western Europe, there was a whole system that allowed you to represent numbers up to 9999 on your fingers.
With the development of civilization, various counting techniques appeared. They were necessary for tax collectors, merchants, artisans, and moneylenders. The art of counting was mastered by a few specially trained people - counters. They used counting instruments - abaci.
The simplest abacus is a board with grooves cut into it.
Abaci were already used in the 5th-4th centuries BC. The word "abacus" is of Greek origin and literally means "dust", although its semantic meaning is "counting board". What's the matter? The answer is simple: initially, the pebbles were laid out on a completely flat board, and to prevent them from rolling off from their original position, the board was covered with a thin layer of sand or dust. And from the word “pebble” (in Latin - “calculus”) comes the name of the modern calculating device - “calculator”.
The abacus was used in both ancient Greece and ancient Rome, and then in Western Europe until the 18th century. It looks like the abacus you are familiar with - bones on metal knitting needles inserted into a frame.
Abacus was used by different peoples, and each people had their own characteristics. Chinese accounts suan-pan there are seven balls on each wire, two of which are separated from the other five. IN Russian accounts there are ten seeds in each row, and in Western European ones there are nine.
In Japan, even today, counting speed competitions are held between people armed with Japanese abacus. soroban, and computer operators. Moreover, as a rule, calculators win. After all, for a machine to start counting, you need to create a program for it.
As time passed, people's needs for processing numerical information increased. The first ideas for mechanizing the computing process appeared at the end of the 15th - beginning of the 16th centuries. This is evidenced by a sketch of a summing device found in the late 60s of the last century, developed by Leonardo da Vinci. Based on these drawings, the American computer manufacturing company IBM has now built a working machine for advertising purposes.
In 1642, the famous French physicist and mathematician Blaise Pascal created and gained enormous popularity the first mechanical calculating machine - an adding machine. (Pascalina)
In 1673, the great German mathematician and philosopher Gottfried Wilhelm Leibniz designed his calculating machine, which allowed not only to add and subtract, but also to multiply and divide multi-digit numbers.
In Russia, the adding machine, created in 1874 by the Russian engineer Vilgodt Odner, successfully competed with the best adding machines from European companies. Its modification “Felix” was produced in our country until the 70s of the twentieth century.
The next important step in the development of computing technology occurred in the 19th century. In 1834, English mathematician and professor at Cambridge University Charles Babbage developed a project for the first programmable computer.
The machine, invented by Charles Babbage, was like a real computing factory. Charles Babbage came up with the idea of using punch cards. In 1985, this machine was built at the Science Museum in London.
In 1890, the Hollerith machine was created, in which the idea of using punched cards was practically realized.
First generation of computers
The first fully electronic computer, Eniak, was built in the USA in 1946. Its dimensions were enormous: more than 30 m in length and 85 m3 in volume. The weight of the car was approximately 30 tons. Data storage and processing in it was carried out using 18 thousand vacuum tubes.
In our country in 1948. year, academician Sergei Alekseevich Lebedev proposed a project for the first computer on the continent of Europe - the Small Electronic Computing Machine (MESM). In 1951 MESM is officially put into operation, and computational problems are regularly solved on it. The machine operated with 20-bit binary codes with a speed of 50 operations per second, had RAM in 100 cells on vacuum tubes. It has about 6000 vacuum tubes (about 3500 triodes and 2500 diodes), occupies an area of 60 m2, and consumes about 25 kW of power.
Second generation of computers
A decade later, in the early 60s, transistors replaced vacuum tubes. The emergence of the second generation of computers is associated with them.
In 1951, the American J. Forreister created Whirewind-1 with memory on magnetic cores.
In 1953, our industry began to produce the Strela electronic computer. The Strela computer, together with auxiliary equipment, occupied an area of 500 square meters. This would be enough for 10 apartments.
In the USSR in 1967, the most powerful second-generation computer in Europe, BESM-6 (Big Electronic Calculating Machine), which could perform 1 million operations per second. BESM-6 used 260 thousand transistors.
Third generation computer
In 1968, the Burrows company in the USA released the first computer running on integrated circuits.
Since the 70s, integrated circuits began to be used. The size of such a circuit is no more than a pea, and it contains thousands of transistors, each of which has dimensions comparable to the thickness of a human hair. The machines shrank so much that they could fit on a desk.
As legend has it, the great-grandmother of the modern mouse was invented in 1968 by Douglas Engelbart. By the way, he also called his device “mouse”.
Fourth stage
The development of high technologies has led to the creation of large integrated circuits - LSIs, including tens of thousands of transistors.
The first personal computer was the App1e-1, created in 1976.
In 1982, IBM began manufacturing IBM PC personal computers (the “grandfathers” of modern IBM-compatible computers).
Modern personal computers compact and thousands of times faster than the first personal computers
4. Homework.
- Uch. pp. 9-10.
- Questions page 10.
- Additionally: Chapter 4 Material for the curious §4.13 -4.18, read.
- Practical work. User Interface Basics: Desktop, Application Window, Computer Control (repeat);
- Working on a keyboard trainer.
- Summing up. Finishing work.
Literature:
- Bosova L.L. Computer Science: Textbook for 6th grade. – M.: Binom. Knowledge Laboratory, 2010.
- http://www.gym075.edusite.ru/istoriyavt.html - Development of computer technology and computer generation.
- http://historyvt.narod.ru/ - Development of computer technology and computer generation.
- http://forum.antichat.ru/thread141014.html - the history of computers, the pictures are a lot of interesting.