Search engine basic function crawl and index

Absrtact: Search engines have two main functions: Crawl and index, and sort the results according to relevance and importance. Imagine that the World Wide Web network stays in the subway system of a big city, every station, its own unique file (usually

The search engine has two main functions: Crawl and index, and sort the result answers according to relevance and importance.

Imagine that the World Wide Web network is stuck in a metro system in a big city.

Every stop is its own unique file (usually a Web page, but sometimes a pdf,jpg or other file). Search engines need a way to "crawl" the entire city to find all the stops along the route, so the best path they use is the link.

1, crawl and index. Crawl and index billions of of documents, Web pages, files, news, videos and media for the World Wide Web.

2. Provide the answer. Provide user inquiries, most often through the relevant pages of the list, through the search and ranking.

By linking, the search engine's robotic robots, known as "reptiles" or "spiders" can reach billions of of interconnected files. Once the engine finds these pages, they will store this information in a snapshot of the mass of hard drives, to allow users to search queries when needed, these servers support the search engine can complete such a huge search task, billions of of pages, can be accessed in a fraction of a second, Search engines have built data centers around the world. These huge storage facilities hold thousands of machines to handle a large amount of information. After all, when a person searches in any major search engine, the results they need instantaneously, or even 1 or 2 seconds of delay, may lead to dissatisfaction, so search engines try to provide as fast an answer as possible.

The search engine is the answer to the machine. When a person searches through a search engine for the information they need, the search engine will find billions of of files in its own database, and do two things at once: first, return queries from searchers whose results are relevant or useful; second, rank these results to provide the most useful results. So, search engine is the provider of the answer, "relevance" and "importance" is indispensable, SEO is to affect these two factors.

A search engine, relevance means more process than simply finding a page. In the early days of the network, search engines did not take into account this simple factor, the quality of its search results can be imagined. Therefore, in the process of evolution, intelligent engineers will search engine design a better way to find valuable results, searchers will be more receptive and satisfied. Today, the impact of SEO on relevance is the most concerned aspect of most people who provide site optimization and keyword ranking techniques.

How does a search engine determine importance?

Currently, the main search engine usually understands the importance of being a more popular web site, Web page or file, and contains more valuable information. In practice, this assumption has been proved to be quite successful, as a search engine continues to use the measurement, is the improvement of the quality of work and rest, and improve user satisfaction.

Popularity and dependencies cannot be determined manually. Instead, the search engine is more and more intelligent, set mathematical equations, algorithms, sorting and other techniques in one, Quweicunzhen, and then according to the importance of the most valuable information in the front.

These algorithms usually include hundreds of small algorithms, in the Search marketing field, we often mention the "ranking factor" of the Web page, just for the main algorithm, many small algorithms to improve or evolve, we are often easy to ignore, but they ultimately deeply affect the whole development of search engine algorithms.