Did you know that when you surf the web, some websites may put secret software（软件）on your computer? The software collects a large amount of information about you and sends it to Internet companies. Then your information will be sold to other businesses.
First, companies collect your information and record all your online habits. They find out where you live, what websites you visit and what you do online. With this information, they can guess other things about you. For example, they can guess if you are a man or woman, how old you are and what you are interested in. Then these companies will show products or other websites to you.
Another way your personal information can be collected is through social media（社交媒体）. When your information is on social media, a lot of people can see it. Even if you don't use social media, a friend might post a picture or video of you with your name on it. This act of sharing could be a problem for your own safety. If someone knows too much about you, they can use your information to buy things online or post messages.
However, it's not all bad news. Rules are finally changing when it comes to technology. In Europe, for example, Internet users can now ask companies to show them what information they have about them and even make them delete（删除）it. If other countries do the same, the Internet could soon be a much safer place.
