A Look On Google Part 1 of 4

The Importance of Search Engines - Historic Review

One might say that the key difference between the online and the real world is that online it is much easier to find things. Whereas in the real world, you might have to look for an almanac, check the index, look for the page and find the information you are looking for – say, Japan’s population –, online you just need to type in a simple query (“What is Japan’s population?”) and the answer is just a click away.

This simple procedure, taken for granted today, was not technologically possible a few years ago. It was not until the arrival of Google that web searching became a user-friendly task that produced outstanding results.

Sure, search engines have existed long before Google, yet the technology that drove them was significantly different. For example Yahoo!, the first popular internet search engine in the 90’s, was actually an online version of the yellow pages: web creators would submit their URL (the address at which a webpage is found), along with a commentary and related keywords. This information was stored in the Yahoo! database and used to produce results when a user typed in a query. But anything not submitted to Yahoo! did not exist on the Yahoo! database, and therefore could not be found.

Then came AltaVista, with a technology that allowed it to briefly become the best search engine available. It employed web-spiders, which are computer programs that automatically scan and index web pages, thus yielding many more results than Yahoo! ever could.
Yet the results where not ranked, and this meant that any simple query returned a vast amount of results, but you then had to sweep through the results in search of the piece of information you were actually looking for.

Google solved this by introducing PageRank. Assuming that an important webpage (say, BBC’s homepage) has more links and more pages link to it, than a less important webpage (say, my personal blog), then PageRank assigns a value to each of the pages it finds on the internet, according to a complex mathematical algorithm involving the hyperlinks between web pages.
This value allows Google to rank pages in order of relevance to the search query. Directly, it meant that users did not have to sort through the result pages to find what they were looking for, as the most relevant results are displayed first on the result pages. Indirectly it meant that other search engines, such as Yahoo! and AltaVista had met a rival that, in just five years, would manage 80% of online searches.

Main Source: The Economist