Search Engine is a software that pinpoint the files (website | web page| blogs etc.) in its Database on the basis of defined Keywords by users and the list of results shows at SERP.
Search Engine do its work in four major parts.
- Crawling
- Indexing
- Retrieval
- Ranking
Crawling
Software has done this task, known as Crawler or a Spider or Googlebot in case of Google search Engine. When a website is developed, it is in the form of codes, which includes pictures, text, audio, video, contents, etc. Crawlers reads entire code of website and store it in Google Database.
Indexing
There is another program named as Indexer, it reads all the data (CODE) and indexed it on the basis of Keywords words given in the code.
Retrieval
It has two main functionality
- Processing
- Calculating Relevance
Processing is a process of search engine to get the meaningful data from its corpus of millions of indexed documents based on keywords or set of words or sentences, mentioned in Online Search.
Calculating Relevance means Search Engine starts relevancy on more than finding a page with the searched Keyword or Sentences in its Index documents.
Ranking
Search Engine updates their mathematics Equations (Algorithm – Penguin, Panda, etc.) to rank the Search Result based on popularity and quality and display at SERP