When you're surfing the Internet on your laptop from your dorm or home, do you know your personal details are being gathered secretly? And would you be surprised to know the information may be sold cheaply to advertisers and marketers? According to an investigation by The Wall Street Journal, all it takes is a tiny file in a computer-a single code consisting of a long series of numbers and letters to record the computer user's age, gender, location, favorite movies and hobbies. The newspaper reports that Lotame Solutions Inc., a New York company, uses sophisticated   software called a " beacon" to capture what people are typing on a website. Lotame packages that data into profiles   about individuals, only without their names, and sells the profiles to companies seeking customers. Batches of such data may be sold for a few dollars. The Wall Street Journal survey discovered that spying on Internet users is one of the fastest-growing businesses on the World Wide Web. The "cookie" a tiny text file put on your PC by websites or marketing firms which might be used to remember your. preferences for one site, or to track you across many sites is already old news. There are new and more complex tools such as "beacons " which scan in real time what people are doing on a webpage. These beacons instantly assess the Internet user's location, income, shopping interests and even medical conditions. Millions of Internet users around the world also face unprecedented   threats. Private, sensitive, personal and business information is being gathered and sold without their knowledge. Companies insist the information they gather is anonymous and the data is used harmlessly. But the technology has grown so powerful that even some of the biggest websites in the US don't know that they were installing intrusive files on visitors' computers. These include MSN. com and Yahoo. com. Next time you visit a webpage and find an ad banner advertising something you've been planning to buy, don't be amazed that your computer can read your mind. The purpose of the passage is to   _  .
introduce a tiny file in a computer-a single code show how your individual information was let out when you surf the Internet show how to protect your privacy introduce a sophisticated software called a " beacon"