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Great Inventions
Television (1920s)
The invention that swept the world and changed leisure habits for countless millions was pioneered by Scottish-born electrical engineer John Logie Baird. It had been realised for some time that light could be converted into electrical impulses, making it possible to transmit such impulses over a distance and then reconvert them into light.
Motor Car (late 19th Century)
With television, the car is probably the most widely used and most useful of all leisure-inspired inventions. German engineer Karl Benz produced the first petroldriven car in 1885 and the British motor industry started in 1896. Henry Ford was the first to use assembly line production for his Model Т car in 1908. Like them or hate them, cars have given people great freedom of travel.
Electricity
The name came from the Greek word for amber and was coined by Elizabeth I's physician William Gilbert who was among those who noticed that amber had the power to attract light objects after being rubbed. In the 19th century such great names as Michael Faraday, Humphry Davy, Alessandro Volta and Andre Marie Ampere all did vital work on electricity.
Photography (early 19th Century)
Leonardo da Vinci had described the camera obscura photographic principle as early as 1515. But it was not until 1835 that Frenchman Louis Daguerre produced camera photography. The system was gradually refined over the years, to the joy of happy snappers and the despair of those who had to wade through friends' endless holiday pictures.
Telephone (1876)
Edinburgh-born scientist Alexander Graham Bell patented his invention of the telephone in 1876. The following year, the great American inventor Thomas Edison produced the first working telephone. With telephones soon becoming rapidly available, the days of letter-writing became numbered.
Computer (20th Century)
The computer has been another life-transforming invention. British mathematician Charles Babbage designed a form of computer in the mid-1830s, but it was not until more than a century later that theory was put into practice. Now, a whole generation has grown up with calculators, windows, icons, computer games and word processors, and the Internet and e-mail have transformed communication and information.
Aeroplane
The plane was the invention that helped shrink the world and brought distant lands within easy reach of ordinary people. The invention of the petrol engine made flight feasible and the American Wright brothers made the first flight in 1903.
Mankind has always had a compelling desire to communicate. In ancient times this could be verbally or in some form of writing. If remote communication was required (i.e. if the parties were not physically together) messages had to be physically carried or sent by a messenger. Examples of early forms of remote transmission of messages not requiring a person to actually move between the sender and the receiver would be in 'jungle drum' or 'smoke signal' transmissions. These were somewhat lacking in security and privacy.
If 'email' is loosely defined as 'messages transmitted electronically', then the first 'email messages' would have started in the last century with telegraph messages (by wire) and Morse Code transmissions (via airways). This definition would also include the telex network that was used extensively by business on a world-wide basis from the mid-1920's to the mid-1980's. The telex network was independent of the telephone network and telex machines could connect with and communicate with any other telex machine on a global scale. Telex also was relatively secure in that the sending and receiving machines did identifying handshaking. It was relatively expensive to have a 'telex line' installed and subsequent telex messages were charged on a data transmitted basis. In addition, for much of its history, use of telex required a dedicated 'telex terminal' which was less than intuitive and often required trained operators. It may come as a surprise to many in this age of computers and chips everywhere that telex is still operating and being used throughout the world.
During the 1960's and 1970's many companies who were using mainframe and mini computers also used email facilities on those systems. This enabled users of terminals attached to those systems to send messages to each other. As companies began to connect their central systems (hosts) to branch offices and subsidiaries then employees were able to send email to other employees of that company on a world-wide basis. Also during this time the US Department of Defense's research into computer networks was well underway, resulting in the embryonic ARPANET --the forerunner to the now global Internet. According to information regarding these early years, the first ARPANET network email message was transmitted in 1971. In the late-1970's and 1980's the phenomenal growth of personal computers (Apple II 1978 - 1985; IBM PC 1983 and Apple Macintosh 1984) created a whole new genre of email technologies. Some of these systems were proprietary 'dial-up' systems such as MCI Mail, EasyLink, Telecom Gold, One-to-One, CompuServe, AppleLink etc. For two people to exchange messages remotely on these systems they had to both be subscribers. The proprietary systems did not interoperate or transmit messages from one system to another, or for the few systems that did these were notoriously unreliable Р a reason for eventual demise of most of these systems. At the same time, companies and enthusiasts were setting up 'bulletin board systems' (BBS) which were often used both to send/receive messages and to exchange information. A couple of facts are worthy of note at this juncture: a) there were over one million Apple II computers sold before the first 'PC' was even released; b) there were hundreds-of-thousands of personal computer users sending and receiving 'email messages' using dial-up systems prior to the Internet becoming available for general use. In parallel with the development of the personal computer market, companies were connecting the personal computers increasingly being used by their staff, to both their mainframe/midrange systems and to "LAN-based" email systems. When connected to the mainframe/midrange systems they were often being used in 'terminal emulation' mode and therefore the email being used was the same as for the dedicated terminals. The LAN-based systems often had much easier-to-use interfaces and offered more functionality, such as the ability to send attachments with email messages. As the company networks slowly evolved from terminal-based host-access applications through to PC work groups, the Internet was becoming more widely used for access to information. Firstly for military use, then academic and commercial communications.
The history of the Internet and its creation is a complex issue. As the Internet became available to more people, both privately and through company connections, the email facilities available to users have evolved from the proprietary email systems available within company networks and via host-based systems through to the current trend of "Intranets" which are effectively private mini-Internets, using the standards-based Internet services, such as mail & web servers in place of proprietary ones. Since 1995 both the Internet and email have been 'hot' topics. But when one cuts away the hype, one realises that email itself is not new. What is relatively new however is that email is now:more readily availableinteroperable between systemsavailable world-widefreemuch better knownreached a critical mass where one can expect others to have an email address(generally) complies with standardsmuch easier to usefashionable
No doubt the Internet will shape future communications, far beyond the current uses. As to what features and functions that will become available over the next few years, the speed of progress dictates that we can only guess.
E-commerce
E-commerce – commerce conducted over the Internet , most often via the World Wide Web. E-commerce can apply to purchases made through the Web or to business-to-business activities such as inventory transfers. A customer can order items from a vendor's Web site, paying with a credit card (the customer enters account information via the computer) or with a previously established "cybercash" account. The transaction information is transmitted (usually by modem ) to a financial institution for payment clearance and to the vendor for order fulfillment. Personal and account information is kept confidential through the use of "secured transactions" that use encryption technology.
In an effort to further the development of e-commerce, the federal Electronic Signatures Act (2000) established uniform national standards for determining the circumstances under which contracts and notifications in electronic form are legally valid. Legal standards were also specified regarding the use of an electronic signature ("an electronic sound, symbol, or process, attached to or logically associated with a contract or other record and executed or adopted by a person with the intent to sign the record"), but the law did not specify technological standards for implementing the act. The act gave electronic signatures a legal standing similar to that of paper signatures, allowing contracts and other agreements, such as those establishing a loan or brokerage account, to be signed on line. Once consumers' worries eased about on-line credit card purchases, e-commerce grew rapidly in the late 1990s. In 1998 on-line retail ("e-tail") sales were $7.2 billion, double the amount in 1997. On-line retail ordering represented 15% of nonstore sales (which included catalogs, television sales, and direct sales) in 1998, but this constituted only 1% of total retail revenues that year. Books are the most popular on-line product order—with over half of Web shoppers ordering books (one on-line bookseller, Amazon.com, which started in 1995, had revenues of $610 million in 1998)—followed by software, audio compact discs , and personal computers . Other on-line commerce includes trading of stocks, purchases of airline tickets and groceries, and participation in auctions.
Cyberterrorism
Defined broadly, the term "computer crime" could reasonably include awide variety of criminal offenses, activities, or issues. The potential scope is even larger when using the frequent companion or substitute term "computer-related crime." Given the pervasiveness of computers in every day life, even in the lives of those who have never operated a computer, there is almost always some nontrivial nexus between crime and computers.
By the FBI's definition, cyberterrorism is well beyond the scope of this paper. With increasing frequency this term is being used by the mass media. Absent any evidence of activity, we'll leave it in the "eye of the beholder" to determine whether cyberterrorism is currently being deterred, is a phantom menace…or somewhere in between.
A key distinction between electronic civil disobedience and politicized hacking is anonymity. The motive for remaining secret is simple: the majority of politically motivated hacks are clearly illegal. Most institutions recognize that breaking into an opponent's computer and adding, changing or deleting (HTML) code, even if it is juvenile graffiti, violates some other's rights. Attitudes and opinions begin to divergemarkedly around this point however. One person's activist is another's terrorist.
"A lot of groups are claiming that they're hacking into sites for ahigher moral purpose, but they're hiding beyond anonymity or pseudonymity. Taking responsibility is not something we see happening."
At the heart of this discussion is the question of motive. Opinions differ just as much within the hacker community as outside over the efficacy of certain actions. The spate of (zombie) DDoS attacks against prominent e-commerce sites that occurred in February 2000 sparked a debate between two prominent hacker collectives. The Electrohippies Collective claims the Internet as a public space liable to be used by groups and individuals as a means of protest. As activists, they admit no practical difference between how cyberspace and the street are used by society.
Recent actions on the Internet against e-commerce sites represent a fundamental disagreement about the purposes of the Internet, and the increasing emphasis on the use of the Net as a vehicle for profitable trade rather than of knowledge and discussion.
The cDc says, the targeted sites were selected for their name recognition and prestige value, not for their commercial attributes or activities.
You may make yourself feel good and get a lot of attention, but when you crack a Web site, you are violating another person's rights. …what does that mean? CRIME!
Computers
When Charles Babbage, a professor of Mathematics at Cambridge university, invented the first calculating machine in 1812 he couldn't even imagine the consequences of this discovery. Nearly everything we do in the world is assisted or even controlled by computers, the complicated descendants of his simple machine. Computers are used more and more often in the world today, for the simple reason that they are far more efficient than human beings. They have much better memory and they can store much information. No man alive can do 500000 sums in one second, but a computer can. In fact, computers can do many of the things we do, but faster and better. They can predict weather, and even play chess, write poetry or compose music. Just as television has extended human sight across the barriers of time and distance, so the computers extend the power of the human mind across the existing barriers.
Computers in medicine
Computers are one of great importance in modern hospital. The chief use of computers is the storing and sorting the medical knowledge which has been acquired in the last 50 years. No doctor can possible keep up with all discoveries. The only solution of the problem is store medical knowledge in a computer. Today there are medical computer centers were all existing knowledge of symptoms of various diseases and of their treatment is stored. Doctors feed data on symptoms in the computer and get the necessary information on correct diagnostics and treatment.
Computers that can be taught
Ordinary computer can use only the data stored in the hard disk. Now scientists have designed machines, that are capable of learning from their experience and remembering what they have learned. Such a machine is capable of recognizing objects without human help or control. But of course, they can make many mistakes.
Computers at the school
Information science with the ideas and message of processing and storing information is of great importance today. That's why computer technology must be taught in secondary school. The new subject "basic information science", and "computing machines" was introduced for the senior pupils at schools. Contact with the machine increases the interest in learning, makes them more serious about studying new subject. School computers are used not only to study information science, but also for examination purposes. Young people who finish the school must be trained to operate computers.
Computer Revolution
50 years ago people didn't even heard of computers, and today we cannot imagine life without them.
Computer technology is the fastest-growing industry in the world. The first computer was the size of a minibus and weighed a ton. Today, its job can be done by a chip the size of a pin head. And the revolution is still going on.
Very soon we'll have computers that we'll wear on our wrists or even in our glasses and earrings.
The next generation of computers will be able to talk and even think for themselves. They will contain electronic "neural networks". Of course, they'll be still a lot simpler than human brains, but it will be a great step forward. Such computers will help to diagnose illnesses, find minerals, identify criminals and control space travel.
Some people say that computers are dangerous, but I don't agree with them.
They save a lot of time. They seldom make mistakes. It's much faster and easier to surf the Internet than to go to the library. On-line shopping makes it possible to find exactly what you want at the best price, saving both time and money. E-mail is a great invention, too. It's faster than sending a letter and cheaper than sending a telegram.
All in all, I strongly believe that computers are a useful tool. They have changed our life for the better. So why shouldn't we make them work to our advantage?
Comets
Made of dust, ice, carbon dioxide, ammonia and methane, comets resemble dirty snowballs. You may remember them as blurry smudges in the sky. Comets orbit the Sun, but most are believed to inhabit in an area known as the Oort Cloud, far beyond the orbit of Pluto. Occasionally a comet streaks through the inner solar system; some do so regularly, some only once every few centuries. Heads and tails As a comet nears the Sun, its icy core boils off, forming a cloud of dust and gas called a head, or coma. Comets become visible when sunlight reflects off this cloud. As the comet gets closer to the sun, more gas is produced. The gas and dust is pushed away by charged particles known as the solar wind, forming two tails. Dust particles form a yellowish tail, and ionized gas makes a bluish ion tail. A comet's tails, like these on comet Halley, always points away from the Sun. Meteor showers When Earth crosses the path of a comet, even if the comet hasn't been around for a few years, leftover dust and ice can create increased numbers of meteors.
Asteroids
Quick quiz: How many planets orbit our Sun? If you said nine, you're shy by several thousand. Scientists consider asteroids to be minor planets - some are hundreds of miles wide (and seldom round). Orbits Most, but not all, orbit the sun in an asteroid belt between Mars and Jupiter. The huge gravitational pull of Jupiter accelerated these asteroids to more than three miles per second - too fast to prevent violent collisions. Otherwise, they might have joined up to form "real" planets. When asteroids collide, fragments sometimes are sent on a collision course with Earth and become meteors.
Size and makeup
The vast majority of asteroids are small, compared with a large one like Ida, this 32-mile-long chunk of stone and iron that was photographed in 1993 by the Galileo spacecraft. Though we normally think of asteroids as crater-makers, they are typically pockmarked with their own impact craters. Scientists divide asteroids into two groups, based on how they appear in infrared images: light and dark. The lightest-looking asteroids are rocky bodies with lots of iron and nickel, and they resemble lunar rocks. The darkest asteroids have high quantities of hydrated minerals and carbon. In the early days of the solar system (some 4.6 billion years ago) asteroids had metallic cores, middle regions of stone and iron, and surfaces of stone. Over time, many of them collided with others and broke apart. The fragments, which became many of today's asteroids, are therefore classified as irons, stony-irons or stony. When an asteroid, or a part of it, crashes into Earth, it's called a meteorite.
Origin
There are two hypotheses about how most of the asteroids formed. One says they broke off of a mother planet that existed between Mars and Jupiter. More likely, however, they represent what space was like before the planets formed, and they are the remnants of that process - bits and pieces that never quite joined together.
The threat of impact
Since the Earth was formed more than four billion years ago, asteroids and comets have routinely slammed into the planet. The most dangerous asteroids are extremely rare, according to NASA. An asteroid capable of global disaster would have to be more than a quarter-mile wide. Researchers have estimated that such an impact would raise enough dust into the atmosphere to effectively create a "nuclear winter," severely disrupting agriculture around the world. Asteroids that large strike Earth only once every 1,000 centuries on average, NASA officials say. Smaller asteroids that are believed to strike Earth every 1,000 to 10,000 years could destroy a city or cause devastating tsunamis. More than 160 asteroids have been classified as "potentially hazardous" by the scientists who track them. Some of these, whose orbits come close enough to Earth, could potentially be perturbed in the distant future and sent on a collision course with our planet. Scientists point out that if an asteroid is found to be on a collision course with Earth 30 or 40 years down the road, there is time to react. Though the technology would have to be developed, possibilities include exploding the object or diverting it. For every known asteroid, however, there are many that have not been spotted, and shorter reaction times could prove more threatening. NASA puts the odds at 1 in 10,000 of discovering an asteroid that is within 10 years of impact. Two programs have been set up to actively search for Near-Earth Objects (NEO's): NASA's Near Earth Asteroid Tracking (NEAT) program, and Spacewatch at the University of Arizona. Also, the Spaceguard Foundation was established in 1996 in Rome. The international organization's goal is to protect Earth from the impacts by promoting and coordinating discovery programs and studies of NEOs. A January report shows that NEOs 1 kilometer or larger are being discovered at the rate of about five a month. The combined goal of these agencies is to find 90 percent of all NEOs 1 kilometer or larger within the next decade.
Youth problems (3)
Youth is a beautiful time. The faces of young people, the young souls and young love – everything is beautiful. We can describe all the amazing attractions of this only period in life, which is usually remembered during all lifetime, but many youngsters say that their life is followed by numerous troubles. Really, there is no life without problems, but we can't make little account of youth problems.
Unfortunately, most of the problems are connected with family relations.
Moms and dads say that teenage rebels just growing up normal. Their parents said it, just as parents say it today.
"Damn kids these days". This phrase is the fad of the adults of all times.
To my mind, each new generation of kids receives negative reviews because of two entwined social dynamics: surliness and rebellion in youth; fear and loathing by parents, whose youth has passed them by.
It's called the generation gap, which pits the impertinence of youth against the attitudes of people over 30, who forget what a pain in the butt they were as kids.
If you look at history, youth has always looked bad from the adult perspective. Sometimes it's because they don't remember all the stupid, dangerous things they did as kids.
Adults always tend to glorify their own past. It explains the reason why they often look down their noses at the next generations. Basically, what these critical adults are saying is, "why can't these kids be like us." It is amazing, but every generation goes through this.
I'm deeply convinced tat if some parents are ready to write off the next generation, they should remember how they behaved as young teenagers and recognize rebellion as a sign of growing up.
But we should admit, there are some dangerous temptations of the youth and only parents can preserve their children from such social evil as alcohol, smoking and even early sex and killing oneself by using drugs.
For example, the former Soviet Union admitted that it had over 200,000 drug addicts. Because of this the government opened several special hospitals for these addicts. There's a big anti-drugs campaign in the country's schools too. Usually drugs come from several places including Western Europe and Afghanistan. Also, some addicts use glue or steal medical drugs from hospitals.
This problem is closely connected with gang-violence. As well as gangs of punks, rockers and hippies, there are ultra conservative gangs, too. They want to stop "the dangerous" influence of teenage culture in our country. But actually they follow the ideas of nationalism and even fascism.
One more acute problem for many young people is smoking. Millions of teenagers know it's bad for them, but they still do it. I think it is rather easy to withstand the influence of those who smoke. We should be simply strong enough to say "no".
Many people offer their way out. Some of them say that teenagers should not be let to the discos because of the danger of drugs; others say that young people should be given more money and more freedom, because everything that is forbidden astonishes.
But in my opinion, one thing is clear: after decades of silence in the Soviet Union we face a lot of urgent problem, which should be solved as soon as it is possible.
Youth problems (2)
What are the main youth problems? Everyone knows and at the same time noone knows. As sand through fingers - youth problems are always changing. Thirty years ago Johnny Rotten sang " Too many problems oh why am I here, I don't need to be me 'cos you're all too clear, well and I can see there's something wrong with you but what do you expect me to do?.. Problems, problems, the problem is YOU!" The idea of that punk styled song is simple clear. All our failures depend on us. Imagine your life without money, can you do that? No fancy clothes, no fashionable clubs, no entertainments, no troubles. Americans say "No mass - no fuss" in such case. Don't you think teenagers depend on money greatly? They are obsessed on their appearance, they need to be clothed fashionable and in modern style. Some of them, who are lacking money prefer to wear jeans and plain clothes, this is their way out. The fashion industry is based on some youth preferences, there is a kind of business in producing special clothes and accessories for teens, Kira Plastinina, for example. Young try to do their best in getting labeled and fancy stuff, they are really crazy about such things. External life may force out their spiritual life, and that are dangerous circumstances. In my point of view, young should pay more attention to their inside world, to develop their selves.
Another youth problem is mutual understanding in their families. It's hardly believable situation when a teen feel comfortable with his relatives, even in a tight-bonded family. Parents want them to be serious, to study hard and to think about their future, but rare senior could understand teen's tormented soul. In past life grown-ups were the same teens, but they don't remember that state. Our parents were bits, hippies, and they struggled for their personal independence, just like us! But things change, tastes grow differ and differ, and we can't understand each other, we lose the connection. If teens could obey they olds implicitly, that'll be very convenient for the last ones. Liberal seniors are absolute rarities, so teens have to look for common language with their parents in any case. We all know the moral disaster of being misunderstood. Try harder - and you'll make friends with your relatives. Sometimes young fall apart with their families and begin to take drugs, alcohol. That is not the reaction on the emotional environment, that is the reflection of tortured inside world. Drug addicts are spread all over the world, but in their majority they are young people. Junkies are used to hang on with the same disappointed people, sometimes they had to steal money or jewelry from their houses, to get the drug. It is obviously damaged way. Normally up-brought youth avoid junkies, and addicts could not find the way-out of their abusement.
There is the proverb which says " A word can kill, a word can save", everything is up to you and your attitude towards people. I don't believe we can't rescue people surrounding us. There are special rehabilitation centers for junkies, anonymous help is offered for people. So don't lose your chance to be safe and sound, to live long and unforgettable lives, and one day you'll be thanked for your compassion paid to drowned people. "Life is very short, there is no time for fussing and fighting my friend" (Paul Mc Cartney )