Friday, October 20, 2017
wikipedia about
wikiHow to Teach Critical Thinking
Three Parts:Encouraging Students to Have an Open MindHelping Students Make ConnectionsTeaching Students About Reliable InformationCommunity Q&A
If you want to teach your students critical thinking, give them
opportunities to brainstorm and analyze things. Classroom discussions
are a great way to encourage open-mindedness and creativity. Teach
students to ask "why?" as much as possible and recognize patterns. An
important part of critical thinking is also recognizing good and bad
sources of information.
Part 1
Encouraging Students to Have an Open Mind
-
1Start a class discussion by asking an open-ended question. Open-ended questions are questions that have more than one right answer. This will allow students to think critically and creatively without fear of getting anything wrong. Show enthusiasm about answers that are outside of the box to encourage students to let their minds expand to different possible ideas.[1]- For example, ask students an open-ended question like, "What would be a good way to get more people to recycle in the school?"
- Whether or not it's realistic, offer praise for an inventive answer like, "we could start to make a giant sculpture out of of recyclable things in the middle of the school. Everyone will want to add to it, and at the end of the year we can take pictures and then break it down to bring to the recycling plant."
-
2Give students time to think things through. Narrow thinking is often the result of rushing to give an answer. For classroom discussions or in-class assignments, give students a few minutes to think clearly before they propose any ideas. For the best results, have students sit quietly and put down their books and pens while they reflect.[2] -
3Make a list naming the pros of two conflicting ideas. Get students out of the mindset that there is always a "right" and "wrong" answer by looking for the good in two contrasting ideas. Make a large list on a chalkboard, white board, or large poster with a column for each idea. Ask students to name positive things for both sides and to think about a possible third option that would use parts of each.[3]- For instance, make columns to name the good things about both a camping trip and a city excursion, then have students think about a happy medium between the two.
Part 2
Helping Students Make Connections
-
1Ask your students to look for patterns. Across various subjects of study, encourage your students to look for patterns and connections. This will help your students tie individual lessons to bigger trends or concepts. Encourage students to point out themes or ideas that they've seen before as they are learning.[4]- For instance, environmental themes may come up in science, history, literature, and art lessons.
-
2Show students a vague picture to get them thinking about their own assumptions. Show your students a picture of something that is a bit vague and have them guess what's happening in the picture. Next, ask them to break down the clues in the picture that led them to this assumption. Finally, ask them to think about how some of their own beliefs or experiences shaped what they thought about the picture.[5]- Explain to your students how the clues and their own personal influences form their final conclusions about the picture.
- For instance, show students a picture of a man and woman shaking hands in front of a home with a "For Sale" sign in front of it. Have students explain what they think is happening in the picture, and slowly break down the things that made them reach that conclusion.
-
3Analyze statements by asking "why" five times. Make a game out of interrogating claims by asking "why?" about it five times. You can apply this to most lesson plans you are teaching, especially in regard to literature or history. Encourage students to do this on their own to get to the root of problems and to think about things more deeply. [6]- If you are studying a book or play, you can ask a question like,
"Why did Bob go to the train station?" and break down the responses in
such a way:
- "To take a train."
- "Why?"
- "To get to the city."
- "Why?"
- "To meet his friend."
- "Why?"
- "Because he missed him."
- "Why?"
- "Because he was lonely."
- On a more advanced level, students will benefit from interrogating their research and work to determine its relevance.
- If you are studying a book or play, you can ask a question like,
"Why did Bob go to the train station?" and break down the responses in
such a way:
Part 3
Teaching Students About Reliable Information
-
1Teach students the difference between opinions and factual statements. Teach your students that any claim they make is considered an opinion until they can provide evidence about it. This evidence might be an experiment that they conduct, or reliable information published by experts. In class discussions and projects, remind your students to back up every claim they make with some supporting data.[7]- For instance, if a student says that there are fewer libraries than there used to be, have them provide some actual statistics about libraries to support their statement.
-
2Help students spot advertisements disguised as information. Disguising product placements as neutral information is a powerful advertising tool that is common today. Show students a simple paid story article or subtle commercial segment to get them to think more critically about that information that is presented to them every day. Ask them to consider the sources of this information and the motivations driving someone to share the information in the first place.[8]- Encourage students to ask the simple question, "Who is sharing this information, and why?"
- For instance, an advertisement for a low calorie food product may be disguised as a special interest television segment about how to lose weight on a budget.
-
3Have students rate a website. In the age of electronic information, it is important to know what websites are offering reliable facts and which ones aren't. Discuss the issue in class, or give students an assignment to look at a website on their own and evaluate it. They should be looking at the following factors:[9]- The date it was published, whether or not it has been updated, and how current the information is. Tell students where to find this information on the website.
- What the author's qualifications are. For instance, a medical article should be written by a doctor or other medical professional.
- If there is supporting evidence to back up what the writer says.
Computer
 |
This article has many issues. Please help fix them or discuss these issues on the talk page.
|
 |
This page or section needs to be cleaned up. The specific problem is: The list of uses needs to be tidied so it does not advertise anything. (June 2017) |
A drawing of a usual modern desktop computer.
Modern computers are very different from early computers. They can do billions of calculations per second. Most people have used a personal computer in their home or at work. Computers do many different jobs where automation is useful. Some examples are controlling traffic lights, vehicle computers, security systems, washing machines and digital televisions.
A computer user can control it by a user interface. Input devices include keyboard, mouse, buttons, and touch screens. Some very sophisticated computers can also be controlled with voice commands or hand gestures or even brain signals through electrodes implanted in the brain or along nerves.
Computers can be designed to do almost anything with information. Computers are used to control large and small machines which in the past were controlled by humans. They are also in homes, where they are used for things such as listening to music, reading the news and writing.
Modern computers are electronic computer hardware. They do mathematical arithmetic very quickly but computers do not really "think". They only follow the instructions in their software programs. The software uses the hardware when the user gives it instructions, and gives useful output.
Computer programs are designed or written by computer programmers. A few programmers write programs in the computer's own language called machine code. Most programs are written using a programming language like C++, Java, and Fortran. These programming languages are more like the language with which one talks and writes every day. The computer translates the user's instructions into binary code (machine code) that the computer will understand and do what is needed.
Contents
History of computers
The Jacquard loom was one of the first programmable devices.
Definition
A computer is a programmable electronic device designed to accept data, perform prescribed mathematical and logical operations at high speed, and display the results of these operations, all under the control of software. Mainframes, desktop and laptop computers, tablets and smartphones are some of the different types of computers. An electronic machine which helps in solving problems quickly and easily. It solves problems according to instructions given to it by the computer user called programs or software. It is a digital machine(that uses binary digits) used in all fields.Automation
Most humans have a problem with math. To show this, try doing 584 × 3,220 in your head. It is hard to remember all the steps! People made tools to help them remember where they were in a maths problem. The other problem people have is that they have to do the same problem over and over and over again. A cashier had to make change every day in her head or with a piece of paper. That took a lot of time and made mistakes. So, people made calculators that did those same things over and over. This part of computer history is called the "history of automated calculation," which is a fancy phrase for "the history of machines that make it easy for me to do this same maths problem over and over without making mistakes."The abacus, the slide rule, the astrolabe and the Antikythera mechanism (which dates from about 150-100 BC) are examples of automated calculation machines.
Programming
Main page: Computer programming
People did not want a machine that would do the same thing over and
over again. For example, a music box is a machine that plays the same
music over and over again. Some people wanted to be able to tell their
machine to do different things. For example, they wanted to tell the
music box to play different music every time. They wanted to be able to
program the music box- to order the music box to play different music.
This part of computer history is called the "history of programmable
machines" which is a fancy phrase for "The history of machines that I
can order to do different things if I know how to speak their language."One of the first examples of this was built by Hero of Alexandria (c. 10–70 AD). He built a mechanical theater which performed a play lasting 10 minutes and was operated by a complex system of ropes and drums. These ropes and drums were the language of the machine- they told what the machine did and when. Some people argue that this is the first programmable machine.[1]
Historians disagree on which early machines are "computers". Many say the "castle clock", an astronomical clock invented by Al-Jazari in 1206, is the first known programmable analog computer. Others say the first computer was made by Charles Babbage.[2] Al - Jazari's showed the zodiac, the solar and lunar orbits, a crescent moon-shaped pointer travelling across a gateway that made some doors to open every hour,[3][4] and five robotic musicians who play music when levers hit them. The length of day and night could be changed (AKA re-programmed) every day in order to account for the changing lengths of day and night throughout the year.[2] Ada Lovelace is considered to be the first programmer.[5][6][7]
The Computing Era
At the end of the Middle Ages, people in Europe thought math and engineering were more important. In 1623, Wilhelm Schickard made a mechanical calculator. Other Europeans made more calculators after him. They were not modern computers because they could only add, subtract, and multiply- you could not change what they did to make them do something like play Tetris. Because of this, we say they were not programmable. Now engineers use computers to design and plan.In 1801, Joseph Marie Jacquard used punched paper cards to tell his textile loom what kind of pattern to weave. He could use punch cards to tell the loom what to do, and he could change the punch cards, which means he could program the loom to weave the pattern he wanted. This means the loom was programmable.
Charles Babbage wanted to make a similar machine that could calculate. He called it "The Analytical Engine".[8] Because Babbage did not have enough money and always changed his design when he had a better idea, he never built his Analytical Engine.
As time went on, computers were used more. People get bored easily doing the same thing over and over. Imagine spending your life writing things down on index cards, storing them, and then having to go find them again. The U.S. Census Bureau in 1890 had hundreds of people doing just that. It was expensive, and reports took a long time. Then an engineer worked out how to make machines do a lot of the work. Herman Hollerith invented a tabulating machine that would automatically add up information that the Census bureau collected. The Computing Tabulating Recording Corporation (which later became IBM) made his machines. They leased the machines instead of selling them. Makers of machines had long helped their users understand and repair them, and CTR's tech support was especially good.
Because of machines like this, new ways of talking to these machines were invented, and new types of machines were invented, and eventually the computer as we know it was born.
Analog and Digital Computers
In the first half of the 20th century, scientists started using computers, mostly because scientists had a lot of math to figure out and wanted to spend more of their time thinking about science questions instead of spending hours adding numbers together. For example, if they had to launch a rocket ship, they needed to do a lot of math to make sure the rocket worked right. So they put together computers. These analog computers used analog circuits, which made them very hard to program. In the 1930s, they invented digital computers, and soon made them easier to program.High-scale computers
Scientists figured out how to make and use digital computers in the 1930s and 1940s. Scientists made a lot of digital computers, and as they did, they figured out how to ask them the right sorts of questions to get the most out of them. Here are a few of the computers they built:| Name | First operational | Numeral system | Computing mechanism | Programming | Turing complete |
|---|---|---|---|---|---|
| Zuse Z3 (Germany) | May 1941 | Binary | Electro-mechanical | Program-controlled by punched film stock | Yes (1998) |
| Atanasoff–Berry Computer (US) | mid-1941 | Binary | Electronic | Not programmable—single purpose | No |
| Colossus (UK) | January 1944 | Binary | Electronic | Program-controlled by patch cables and switches | No |
| Harvard Mark I – IBM ASCC (US) | 1944 | Decimal | Electro-mechanical | Program-controlled by 24-channel punched paper tape (but no conditional branch) | No |
| ENIAC (US) | November 1945 | Decimal | Electronic | Program-controlled by patch cables and switches | Yes |
| Manchester Small-Scale Experimental Machine (UK) | June 1948 | Binary | Electronic | Stored-program in Williams cathode ray tube memory | Yes |
| Modified ENIAC (US) | September 1948 | Decimal | Electronic | Program-controlled by patch cables and switches plus a primitive read-only stored programming mechanism using the Function Tables as program ROM | Yes |
| EDSAC (UK) | May 1949 | Binary | Electronic | Stored-program in mercury delay line memory | Yes |
| Manchester Mark 1 (UK) | October 1949 | Binary | Electronic | Stored-program in Williams cathode ray tube memory and magnetic drum memory | Yes |
| CSIRAC (Australia) | November 1949 | Binary | Electronic | Stored-program in mercury delay line memory | Yes |
EDSAC was one of the first computers that remembered what you told it even after you turned the power off. This is called (von Neumann) architecture.
- Konrad Zuse's electromechanical "Z machines". The Z3 (1941) was the first working machine that used binary arithmetic. Binary arithmetic means using "Yes" and "No." to add numbers together. You could also program it. In 1998 the Z3 was proved to be Turing complete. Turing complete means that it is possible to tell this particular computer anything that it is mathematically possible to tell a computer. It is the world's first modern computer.
- The non-programmable Atanasoff–Berry Computer (1941) which used vacuum tubes to store "yes" and "no" answers, and regenerative capacitor memory.
- The Harvard Mark I (1944), A big computer that you could kind of program.
- The U.S. Army's Ballistics Research Laboratory ENIAC (1946), which could add numbers the way people do (using the numbers 0 through 9) and is sometimes called the first general purpose electronic computer (since Konrad Zuse's Z3 of 1941 used electromagnets instead of electronics). At first, however, the only way to reprogram ENIAC was by rewiring it.
Nearly all modern computers use the stored-program architecture. It has become the main concept which defines a modern computer. The technologies used to build computers have changed since the 1940s, but many current computers still use the von-Neumann architecture.
Microprocessors are miniaturized devices that often implement stored program CPUs.
In 2005 Nokia started to call some of its mobile phones (the N-series) "multimedia computers" and after the launch of the Apple iPhone in 2007, many are now starting to add the smartphone category among "real" computers. In 2008, if smartphones are included in the numbers of computers in the world, the biggest computer maker by units sold, was no longer Hewlett-Packard, but rather Nokia.[source?]
Kinds of computers
There are many types of computers:- personal computer
- Workstation computer
- mainframe computer
- minicomputer
- supercomputer
- embedded system
- Tablet computer
There are bigger computers that many people at a time can use. These are called "Mainframes," and these computers do all the things that make things like the internet work. You can think of a personal computer like this: the personal computer is like your skin: you can see it, other people can see it, and through your skin you feel wind, water, air, and the rest of the world. A mainframe is more like your internal organs: you never see them, and you barely even think about them, but if they suddenly went missing, you would have some very big problems.
An embedded computer, also called embedded system is a computer that does one thing and one thing only, and usually does it very well. For example, an alarm clock is an embedded computer: it tells the time. Unlike your personal computer, you cannot use your clock to play Tetris. Because of this, we say that embedded computers cannot be programmed, because you cannot install more programs on your clock. Some mobile phones, automatic teller machines, microwave ovens, CD players and cars are operated by embedded computers.
All-in-one PC
All-in-one computers are desktop computers that have all of the computer's inner mechanisms in the same case as the monitor. Apple has made several popular examples of all-in-one computers, such as the original Macintosh of the mid-1980s and the iMac of the late 1990s and 2000s.Common uses of home computers
- Playing computer games
- Writing
- Solving mathematics
- Looking for things on the Internet
- Watching TV and movies
- Listening to music
- Communicating with other people
- Downloading
- Sending e-mail
- Sorting
- Recording
- Calculating
- Editing (Video, Photo)
- Taking Pictures (photography)
- Drawing
Common uses of work computers
- Word processing
- Spreadsheets (Excel)
- PowerPoint Presentations
- Photo Editing (Photoshop, GIMP)
- Video editing/rendering/encoding
- Audio recording
- System Management
Working methods
Computers store data and the instructions as numbers, because computers can do things with numbers very quickly. These data are stored as binary symbols (1s and 0s). A 1 or a 0 symbol stored by a computer is called a bit, which comes from the words binary digit. Computers can use many bits together to represent instructions and the data that these instructions use. A list of instructions is called a program and is stored on the computer's hard disk. Computers work through the program by using a central processing unit, and they use fast memory called RAM as a space to store the instructions and data while they are doing this. When the computer wants to store the results of the program for later, it uses the hard disk because things stored on a hard disk can still be remembered after the computer is turned off.An operating system tells the computer how to understand what jobs it has to do, how to do these jobs, and how to tell people the results. Millions of computers may be using the same operating system, while each computer can have its own application programs to do what its user needs. Using the same operating systems makes it easy to learn how to use computers for new things. A user who needs to use a computer for something different, can learn how to use a new application program. Some operating systems can have simple command lines or a fully user-frendly GUI.
The Internet
One of the most important jobs that computers do for people is helping with communication. Communication is how people share information. Computers have helped people move forward in science, medicine, business, and learning, because they let experts from anywhere in the world work with each other and share information. They also let other people communicate with each other, do their jobs almost anywhere, learn about almost anything, or share their opinions with each other. The Internet is the thing that lets people communicate between their computers.Computers and waste
A computer is now almost always an electronic device. It usually contains materials that will become electronic waste when discarded When a new computer is bought in some places, laws require that the cost of its waste management must also be paid for. This is called product stewardship.Computers can become obsolete quickly, depending on what programs the user runs. Very often, they are thrown away within two or three years, because newer programs require a more powerful computer. This makes the problem worse, so computer recycling happens a lot. Many projects try to send working computers to developing nations so they can be re-used and will not become waste as quickly, as most people do not need to run new programs. Some computer parts, such as hard drives, can break easily. When these parts end up in the landfill, they can put poisonous chemicals like lead into the ground water. Hard drives can also contain secret information like credit card numbers. If the hard drive is not erased before being thrown away, an identity thief can get the information from the hard drive, even if the drive doesn't work, and use it to steal money from the previous owner's bank account.
Main hardware
Computers come in different forms, but most of them have a common design.- All computers have a CPU.
- All computers have some kind of data bus which lets them get inputs or output things to the environment.
- All computers have some form of memory. These are usually chips (integrated circuits) which can hold information.
- Many computers have some kind of sensors, which lets them get input from their environment.
- Many computers have some kind of display device, which lets them show output. They may also have other peripheral devices connected.
Largest Computer Companies
| Company name | Sales (US$ billion) |
|---|---|
 Apple |
220,000 |
 Samsung |
212,680 |
 Foxconn |
132,070 |
| HP (Hewlett-Packard) |
112,300 |
| IBM |
99,750 |
 Hitachi |
87,510 |
| Microsoft |
86,830 |
| Amazon |
74,450 |
| Sony |
72,340 |
| Panasonic |
70,830 |
| Google |
59,820 |
| Dell |
56,940 |
| Toshiba |
56,200 |
| LG |
54,750 |
| Intel |
52,700 |
References
- Don't confuse the Analytical Engine with Babbage's difference engine which was a non-programmable mechanical calculator.
- a Kempf, Kar (1961). "Historical Monograph: Electronic Computers Within the Ordnance Corps". Aberdeen Proving Ground (United States Army).
- a Phillips, Tony (2000). "The Antikythera Mechanism I". American Mathematical Society. Retrieved 2006-04-05.
- a Shannon, Claude Elwood (1940). "A symbolic analysis of relay and switching circuits". Massachusetts Institute of Technology.
- a Digital Equipment Corporation (1972) (PDF). PDP-11/40 Processor Handbook. Maynard, MA: Digital Equipment Corporation.
- a Verma, G.; Mielke, N. (1988). "Reliability performance of ETOX based flash memories". IEEE International Reliability Physics Symposium.
- a Meuer, Hans; Strohmaier, Erich; Simon, Horst; Dongarra, Jack (2006-11-13). "Architectures Share Over Time". TOP500. Retrieved 2006-11-27.
- Stokes, Jon (2007). Inside the Machine: An Illustrated Introduction to Microprocessors and Computer Architecture. San Francisco: No Starch Press. ISBN 978-1-59327-104-6.
Subscribe to:
Posts (Atom)