Search engines are an online service for finding content on the World Wide Web. Search engines crawl the World Wide Web for documents (webpages) and store what they find in a database. The search engine then provides an interface at a website - a search box and an search button - to query their database of stored documents. At present, 2014, Google and Bing have the largest market share of daily search queries.
To query a search engine is simple: all a user needs to do is visit the search engine's website using a web browser, and then enter a keyword or keywords into the search box and click the search button. Once the user clicks the search button, the search engine will use the keyword entered to query their database for the most accurate result. Google and Bing are popular search engines because they store billions of documents in their databases and return accurate search results.
To successfully query a search engine, a user needs to select an accurate keyword which corresponds to the subject they want to find information about. For example, if a user wants to find information about 'manchester united': an accurate keyword would obviously be 'manchester united'; rather than 'football' or 'soccer' or 'premiership football team'. However, if a search engine does not have a webpage in it's database which corresponds to the keyword used, then it does not matter how accurate the keyword is.
1. The first keyword in a search query is deemed the most important.
2. The more keywords used, the more accurate the search results will be.
3. Virtually every keyword used in a search query (term) is important, but, some may be ignored, such as: 'the' 'for' or 'a'.
4. Some search engines are case insensitive: so using capital letters maybe pointless.
5. Search engines may automatically filter some offensive words.
6. Search engines use an IP address to regionalise a search query. Users may wish to change their geographical location - within a search engine's settings - to search for subjects for a specific geographical region.
7. Search engines can create a search history related to your computer or user account; so you may wish to delete your cookies if you feel your search history is effecting the relevancy of your search results.
8. Search engines have syntax for creating advanced search queries. They are referred to as search operators, and they will be highlighted below.
The following operators and punctuation can be used within Google, Yahoo! and Bing (as of 2014). Search engines do differ in the operators they provide for advanced search queries, but, the following operators are widely available in most search engines.
1. - the dash symbol is put infront of keywords which should be ignored.
comet asteroid -shop - this will separate a search for 'comet asteroid' and 'comet shop', and will ensure webpages for the 'comet shop' are excluded.
2. NOT this word (in caps) is put infront of keywords which should be ignored.
comet asteroid NOT shop - this will separate a search for 'comet asteroid' and 'comet shop', and will ensure webpages for the 'comet shop' are excluded.
3. " " - use quotes to search for a specific phrase.
"all the world's a stage" - the quotes will ensure that the search engine searches for the line from a book.
4. + the plus symbol indicates that the keyword is essential.
london +football +club - the plus symbol tells the search engine not to ignore the keyword it is put infront of. With popular keywords like 'london', webpages unrelated to 'football' and ''club' may be returned without a + symbol used.
5. OR will display results for both keywords it is placed between.
blood type a OR o - will return results for 'blood type a' and 'blood type o', and will ignore search results for other blood types.
6. AND will find webpages which contain all of the keywords.
olympics 2008 AND 2012 - will find webpages which describe the link between two olympic games, rather than just for a single year.
7. site: search a website for a keyword.
email site:bbc.co.uk - this query will search for 'email' webpages located at the domain name (website) internet-guide.co.uk (the current website). If a user simple enters the query 'site:bbc.co.uk' then the search engine will simple list all the webpages that it has crawled and indexed from that domain; this may include doorway pages.
8. link: finds the websites that link to a specific domain name.
link:bbc.co.uk - this query will show all the websites that link to the bbc.co.uk websites; although some search engines may omit a full list of backlinks for a given domain. Links from an external website are referred to as an inbound link (sometimes as a deep link) and the amount of links a website has is termed: link popularity.
9. related: finds websites that are similar in subject and topic.
related:bbc.co.uk - this query will find websites which are similar to the bbc.co.uk website; which will be news websites in the United Kingdom.
10. cache: will display a saved image of the webpage in question.
cache:bbc.co.uk - will display a recent image of the bbc.co.uk homepage; usually the last time the search engine crawled the webpage in question.
11. # when the hashtag is put infront of keywords, it searches for trending topics.
#world cup - this search query will search for the latest trending topics in social media related to the world cup.
Search engines display their search results differently; however, it's fair to say that they generally adhere to a similar structure. Below, we will examine how Google displays it's results (Yahoo! and Bing follow a similar structure). The search results generated by a search engine are referred to as a: search engine results page (SERP).
1. Is the hyperlink to the document and the title of the document
2. Is a description of the document, usually made up from the meta tag description.
3. Is the URL (address) of the document.
4. Is a screenshot of the document, held by Google during it's crawl of the document.
5. Provides a list of documents with a similar type of content.
6. The top result Google displays sometimes includes a list of other popular documents at that domain.