Mapa mental
Search Engines
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Search Engines
How to tell and check that a website is reliable
- Look for websites with established institutions
- Avoid commercial/ advertisement sites
- Look for sites with expertise
- Check the date
- Check the web address
How to narrow down your search
- Use more than one word
- Request to specify certain words by using the plus/ minus sign in front of the desired words
- Use words that are unusual and are popular to the topic that don't show up together in other contexts
- search the tool list to specify the words to a certain category e.g. time
Search Engines
- A search engine is a programme that searches forand identifies items on the worldwide web that have been specified by the user
- The search engine does not run your search in real time because there are billions of new websites being created every minute and if it were to, it'd take forever.
- They are constantly scanning the World Wide Web (WWW) in advance, recording the information for your search later.
WWW
- The internet is a web of pages connected to eachother by hyperlinks
- Search engines are constantly running a programme called a spider.
- Spiders crawl through all the webpages, collecting information about them. Each time it finds a hyperlink it follows it until it has visisted every page it can find on the internet.
- For each page the spider visits, it records any information that it might need for a search ina aspecial databasecalleda search index.
Ranking with Results
- When the user searches for something onthe search engine, it looks up each of those words in the search index, which usually returns millions of results.
- To find the best matches from the search index, the search engine might need to guess what you are looking for.
- Each search engine has it's own ranking algorithm based on what it thinks you want.
- Websites often make money when you visit them so spammers try to game the search algoritm so that their websites are listed higher in the results. So search engines reguarly update their algorithms to prevent fake or untrustworthy sites from reaching the top.
- Search engines are always evolving to return results better, faster and more recent ones by using informatio that the user didn't explicitly provide (like location).