History of search engines

• Archie was the first well developed search engine in the year 1990. It used to search files by matching their names and indexing on FTP server.
• In 1992 Veronica search engine was developed for Gopher based websites.
• Later in 1993 W3Catalog and Aliweb were formed which were web search engines. WebCrawler search engine was the first to allow users search keywords.
• Finally in 1994, the search engine Yahoo! was developed which gained immense popularity. Earlier it was just a directory but in 1995 search feature was also added.
• In 1998 when Google was founded as till now is the most used and preferred browser all across the globe. However, there have been other frequently used search engines formed after google like, Baidu, Bing, Yandex, etc.

Imagine you are in a library and are looking for a particular book. Now if you have to go through every book in each category, it will be a tedious and difficult task. Moreover, if the library has more than a million books then this task seems next to impossible. You are definitely going to need a librarian who can bring the relevant books for you without any delay. Well, that’s where a search engine comes in.

Search engine spamming refers to the practice of creating Web pages, or sets of Web pages, designed to get a high relevance rank for some queries, even though the sites are not popular sites. Popularity ranking schemes such as PageRank make the job of search engine spamming more difficult, since just repeating words to get a high TF– IDF score was no longer sufficient. However, even these techniques can be spammed, by creating a collection of Web pages that point to each other, increasing their popularity rank. Techniques such as using sites instead of pages as the unit of ranking (with appropriately normalized jump probabilities) have been proposed to avoid some spamming techniques, but are not fully effective against other spamming techniques. The war between search engine spammers and search engines continues even today.

The hubs and authorities approach of the HITS algorithm is more susceptible to spamming. A spammer can create a Web page containing links to good authorities on a topic, and gains a high hub score as a result. In addition, the spammer’s Web page includes links to pages that they wish to popularize, which may not have any relevance to the topic. Because these linked pages are pointed to by a page with high hub score, they get a high but undeserved authority score.