Computers in Numbers
THE WORLD OF COMPUTERS IS ALL ABOUT large numbers. There are over 1 billion personal computers in the world, and each one can hold the same amount of information as thousands of books and transfer it to other computers at a rate of several books per second. Over the years, the number and power of computers has grown rapidly—there are more than 100 times as many personal computers in 2011 as there were in 1971.
A BYTE-SIZED WORLD
Computers store data as units of information known as bits—short for binary digits. A bit can have only two possible values—zero or one. Eight bits make one byte, which can store a single character of text or a single numeral. One kilobyte (1 KB) is not 1,000 bytes, but 1,024. This is because computers don’t count in 1,000s, but in binary. A computer can write the numbers 0-1,023 with 10 digits in binary (1,023 in binary is 1111111111). To write 1,024, it would need an eleventh digit, making 10000000000. It organizes its data by allocating data to memory slots in multiples of 1,024 for this reason. This idea is the same at the next levels, where 1 megabyte is 1,024 KB, and so on. Soon, our computer applications will be using petabytes (or 1,024 PB), then exabytes, zettabytes, and yottabytes—each 1,024 times larger than the last.
Although it took them several years to catch on, cell phones have grown rapidly in popularity over the last few decades. Initially, the largest growth was in the developed world. In recent years, the maximum growth in the use of cell phones has been seen in the developing world. Here, the population is growing faster, and setting-up mobile connections is much cheaper than constructing land-based networks.
A SOCIAL WEB
The invention of the web in 1990 has allowed people to communicate easily with each other across the globe. Social networking websites, such as Facebook, MySpace, and Orkut, allow people to stay connected with friends, meet new people, play games, and share pictures and videos. This map shows the most popular social networking websites in different parts of the world. Local social networks are popular in some parts of the world. This is mainly because people find it easier to communicate with their friends in their own language. But with the development of automatic language translation software, the popularity of these local websites may begin to wane.
Predicting the future is tricky, especially where computers are concerned. Many people in the past claimed that there was no reason why people would want computers in their homes. These people and their beliefs were proven wrong and the number of personal computers grew from 101 million in 1990 to more than 1 billion in 2010. Even today, people are unsure if this boom will continue. Some believe that the growth in computer numbers will soon slow because most people will already own computers. Others, however, predict that the number of computers will continue to rise dramatically.
THE LAW OF THE COMPUTER
Ever since the integrated circuit was invented in 1958, the number of transistors that can be crammed onto a chip (a miniaturized integrated circuit) has roughly doubled every two years. Gordon E. Moore, a founder of Intel Corporation, commented on this kind of trend in 1965. Although he wrongly predicted the increase would be twice as fast in the future, the doubling-every-two-years rule has become known as Moore’s Law. It is now so well accepted that computer companies plan future products based on this assumption. The sizes of transistors continue to fall. If Moore’s Law holds true, then by 2020, computers may be using transistors the size of molecules—the tiny units that make up matter!
From country to country, information flows over the Internet at very different speeds. In late 2009, the leader in terms of speed was Japan. The Internet speed was so fast in Japan that an 8-megabyte file could be downloaded in just over a second. The reason for Japan’s fast Internet speed is the government’s willingness to invest in technologies for improving the rate of data transfer. Compared to Japan, the US and UK lag far behind.
Googling—searching for information on Google’s search engine—is an international habit. Each search causes a small amount of heat to be produced in the main Google servers, but how small is small? According to Google, this amount is about 1 kilojoule of heat energy—the examples on the right are based on this estimate. In addition to this, more heat is generated by the user’s computer and the cables that link it to the Google computers.
As the number of web pages grew, it became harder to find information of interest. Search engines were developed to pinpoint the right web pages. Early engines used web crawlers—software that reads text on a web page and indexes it, before moving to the next one. Modern search engines, such as Google, still use web crawlers to find pages, and also complex mathematics to highlight the ones that might be most suitable in response to a particular search.