The Mechanics Behind Filtering

To understand the concept of filtering, one has to understand the meaning of word "appropriate" because filtering is actually the process of selecting and displaying the webpages that are appropriate to the search criteria of the search engines. Basically search engines are always on the look out for relevant and appropriate content in a website, and in order to get that content, the search engines indulge in filtering while indexing the websites. Just like some movies are banned from viewership due to inappropriate content and images, similarly the search engines too ban and restrict certain sites on the basis of irrelevant and inappropriate content. They reach the decision regarding a site being inappropriate when they filter the site.

Different Ways of Filtering:

1. One possible way of filtering is by an ISP where the users get a message that the site is banned, or network problem, or connection timeout.And in case the search string itself contains forbidden words, the search will not be performed and the reason will be shown to the user.
2.Filtering by using whitelists and blacklists when it is the simple keywords that need to be filtered. Whitelists are those sites matching the particular keywords that users are explicitly permitted to visit and all other traffic is blocked. Blacklists, on the other hand, are those sites that match the criteria for forbidden keywords, and users are not allowed to visit.
3. Another way of filtering is using the meta tags. Meta tags are used by many other search engines, but not by Google. Thus if a forbidden keyword is contained in the meta tag, the page will not be displayed in the search results, or will be shown very much behind in the SERPs(search engine result page).
4. Filtering of forbidden keywords by content analysis is one of the most effective, and powerful way. This filtering is done on the basis of profile describing what content can be included and what content can be skipped in search results. The profile is considered a query and the results that match this query are retrieved from the search engines. In other words, it is dynamic content filtering on the basis of the search query of the users. When search results are retrieved from the search engines and matched against the profile, anything and everything that does not match the profile is deleted from the search results.

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