Online searches are carried out by entering keywords in search engines. In order for the researcher to obtain the optimal search result, search queries can be improved in the way they are entered and through search phrases and special search commands.
In a simple search query, the searcher enters a search term in the search field. For example, if the searcher is looking for printer cartridges, he enters this keyword. Depending on the search engine, over a million search results are listed in the results pages( SERP). If the search query requires exact spelling, including upper/lower case, of the keyword or a search phrase, then the keyword is placed in quotation marks:" LTE as 4G technology".
The searcher receives an improvement in the search results for context-based search queries if he uses a second keyword to narrow down the selection. In the case of printer cartridges, he could additionally enter the keyword inkjet printer. This would reduce the number of search results to one fifth. A further concentration of search results would, for example, massively reduce the number of search results by adding a third keyword, "inexpensive".
Combined search queries can be significantly refined by logically linking the search terms using conjunction, disjunction and negation. For this purpose, the search terms are linked with logical operands AND, OR and NOT: LTE AND UMTS, or LTE NOT GPRS, or in the combination of two logical links: (LTE AND UMTS) OR GPRS. The complete search input with all characters, digits, search words and their links is called search string.
With Web 3.0, the keyword search query is increasingly being replaced by the semantic search query. It should also be possible to enter questions.
As far as special search commands are concerned, the search engines use their own syntax. At Google, for example, there are various search commands such as Allinanchor, Allintitle, Allintext and Allinurl. If one of these search commands is used in combination with a search word - for example, Allintitle:Knowledge - then all web pages with the word Knowledge in the title are listed in the results lists. In the other cases, all web pages with links to knowledge or all web pages with the word knowledge in the Internet address( URL).