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Hunting for treasures: Search Engines
How many different kinds of dinosaurs were there, anyway? How does calculating percentages work exactly? What songs has a certain singer already released? And what is the Spanish name for mustard?
You can find answers to all the questions you can think of on the Internet. But in order to quickly get exactly the right ones, you should know how to use search engines. The best known search engines are Google, Bing and Yahoo. If you want to protect your privacy, you can use DuckDuckGo, a search engine which claims not to collect personal information. Ecosia, a search engine whose creators say they support the planting of new trees around the world, is also popular with many.
The basis for search engines are special computer programs that search all the websites that exist, 24/7. These programs are called web crawlers. They crawl through every page like spiders and put all the information they find into a list called the index.
If you type a question into the search box, the search engine only has to look in that index for the keywords. This is much faster than evaluating all pages anew each time. For example, if the question is “How many species of dinosaurs were there?” the engine will find all entries in the index that contain the words dinosaur and species.
Which of these entries are shown at the top of the list is decided by algorithms. These are instructions that are executed one after the other to solve a task. Almost like a treasure hunt. The algorithm checks which pages on the subject of dinosaurs are particularly trustworthy, which ones contain a particularly large amount of information and whether these pages are also recommended elsewhere on the net. The ones that best match the search query are shown first. But be careful: At the top of the results list in many search engines you will still see ads – the entries that companies have paid for. They are not always the best source for the information you are looking for.
What does a search engine know about me?
Did you ever enter your own name into a search engine? If not, by all means try: For most people, it's amazing how much information is available online. The school you attended, for example, your address, friends from chat forums you're connected to, or party pictures. Most of the time, users have entered the infos themselves somewhere, often in social networks. They can mostly be found by anyone for a long time via search engines.
What does the search engine do with informations about me?
Search engines use the data they collect to improve their search results. If a user clicks on the first result of the search and immediately goes back to the search engine, the result was probably not good. The search engine then tries to improve its results. It also uses the data for spell-checking and to develop new suggestions for word combinations that many people search for. To make surfing the Internet easier and to prevent criminals from stealing passwords and other data, search engines also store cookies on users' devices. Unfortunately, this type of cookies are not exactly tasty, but they help to recognize individuals on the web. In addition, they are also used to tailor advertisements to the respective users.
How can I use filters in search engines?
You can set up security filters for all search engines. At Google and Bing the filter is called SafeSearch, at Yahoo family filter. The filters ensure that no brutal or disgusting content is displayed. All major search engines offer a three-step filter:
1. filter offensive text, images and videos
2. filter offensive images and videos
3. no filtering of search results
The filters of the search engines are mainly based on algorithms. However, the settings are easy to undo. They can only be permanently installed through a personal account with the respective search engine.
Which search engines are recommended for children?
There are specific children's search engines so that younger children can easily search for content that is suitable for them. They only show pages that have been checked by experts and are designed for particularly young users.