Assignment :

Features of the Google Search Engine

Subject:

CS-100 ICT

Prepared By:

Waleed Liaqat

CE-2011/ Sec- C/116955

Submitted to:

Lec. Bilal

Date Submitted:

03-10-2011

What is the Google search engine?

Let’s start by defining what a search engine is. A search engine is a program that

searches and fetches documents that contain certain keywords or the search

criteria which you communicate to the engine through its interface.

The Google search engine is a creation of the multinational corporation Google.

Google search engine started out as a research project. Today, however, it has

become the most widely used search engine on the planet. This is due to its

simple design and ease of use, but more importantly it is because of the search

engine’s capabilities and unique algorithm that gives efficient results, that it is the

choice of billions across the planet.

How it works?

Once you specify the search criteria or keywords, this information is sent to the

Google web server which uses it to search its index of webpages and collects

webpages that match the given criteria. These webpages or websites are then

arranged in order of their relevance by a program called PageRank. This is the

very programme that gives Google an edge over other search engines. The results

once sorted are displayed with the relevancy information as well as information

such as total results and time taken to search and display.

Google’s index server contains billions of webpages. The index is updated

regularly through programs called crawlers.

Although Google search engine provides fast results, the results may contain the

search criteria but the webpage in its entirety may not be relevant to us. In such a

case, to narrow down our searches we use certain symbols such as the hyphen,

each of which serve a certain purpose.

We can further understand some of the features of Google search engine and

how it works through examples on the next few pages.

Problem 1: Searching for a webpage that contains one or the other element of

the search criteria.

Solution : Use of the pipe symbol (|)

Queries : Peter Pan [fig. 1(a)], Peter|Pan [fig. 1(b)]

Fig . 1(a) Entering ‘Peter Pan’ gives

the following results. The listed

webpages contain both search

terms.

What’s happening:

When we use ‘ peter pan’ as our search terms, webpages displayed as search

results contain both the search terms, however when we use the pipe symbol (|)

to separate ‘peter’ and ‘pan’ and search, the results are different and it is evident

that the pipe symbol works as an ‘OR’ operator. Use of this operator allows us to

expand our search results pool.

Fig. 1 (b) shows the result when

we include the pipe symbol

between peter and pan.

Problem 2: Searching with terms which can have different interpretations in

different scenarios e.g. ‘virus’ has a different meaning when we relate it to

computers but a whole other meaning when we relate it to medical science.

Another example is that of searching for Sagittarius which is the name of a

constellation and a horoscope which are completely different concepts.

Solution: Use of Hyphen symbol (-)

Queries: Sagittarius [fig. 2(a)], -Constellation Sagittarius [fig. 2(b)].

Fig. 2(a) Search results for Sagittarius.

What’s happening:

When we search for ‘Sagittarius’, the results returned contain webpages where it

is present in relation to constellation or horoscope or both. To narrow our search

results or to look for webpages where it is only explained as one of the twelve

horoscopes we use the hyphen symbol (-) before constellation, which leads to

exclusion of any webpage from the results pool that contains a reference to the

collection of stars given the name Sagittarius.

Fig. 2(b) Search results for Sagittarius

when we use the hyphen symbol to

eliminate the term constellation

from our results pool.

Problem 3: Searching for news or information from a particular period of time.

Query: PIA crash incidents between August 1979 and December 1984. (news)

Solution: Using timeline feature. (fig. 3)

Enter the period of time for

which the information of

PIA crash incidents is

required to get results.

Entering the given Query in

the search engine

(ordinarily) gives results

regarding various crashes

of the PIA including those

which do not fall into the

period of time specified.

Fig. 3

What’s Happening:

Normally when we enter ‘ PIA crash incidents between August 1979 and

December 1984’ in the search engine, we get news articles on incidents that

belong as well as incidents that don’t belong to the specified time period. Also,

use of ‘between’ doesn’t ensure that the results pool will contain news reports

from within the specified time period. In such cases, we use Google search tools,

specifically, the timeline feature which will ensure that only news from the

specified period is shown as a result.

Problem 4: Searching for webpages containing exactly all of the search terms

Solution: Use of Quotation marks (“”)

Queries: Everything is fair in love and war [fig. 4(a)], “Everything is fair in love

and war” *fig. 4(b)].

Fig . 4(a) Search results for

first query.

What’s happening :

When we search for ‘Everything is fair in love and war’, we get results like ‘All’s

fair in love and war’. Both of these have essentially the same meaning. The

replacement of ‘Everything’ with ‘All’ is known as stemming, a default process

performed by the Google search engine in which it displays results which contain

synonyms or variants of certain search terms. This process is stopped by use of

quotation marks on our query. The use of the quotation marks allows only those

results to be shown which contain the phrase ‘Everything is fair in love and war’

exactly but not necessarily as a complete phrase.

Fig. 4(b) shows the results when

quotation marks are added to the

first query.

Problem 5: Searching for complete information when we are only given part of

the information to use as a search term.

Solution: Use of asterisk (*)

Queries: Fear of a itself [fig. 5(a)], Fear of a * itself [fig. 5 (b)].

(Quote of J.K. Rowling, author of Harry Potter: ‘Fear of a name increases fear of

the thing itself.’)

Fig. 5 (a) Search for first query does not generate

results relevant to you.

Fig. 5 (b) Search for first

query with the use of

asterisk gives webpages

that contain the quote

required.

What’s happening:

When we search for the required quotation using the search terms ‘fear of a

itself’ , we get webpages that give information on movies. By combining the

asterisk with the initial query, we specify that we are searching for a sentence or a

phrase rather than individual terms. It also shows that we are missing a portion of

the quote or dialogue required. This should be used when you can only recall a

portion of the information required.

Problem 6: Expanding your search results pool without using synonyms or

variants of the search terms.

Solution: Use of the Tilde symbol (~)

Query: Biology is ~tough [fig. 6]

Fig. 6 shows results when

we search for ‘ Biology is ~

tough’.

What’s Happening:

When we perform the search with the words ‘Biology is tough’, we mostly get

webpages that contain all three words. In order to expand our results pool and to

select the information we need from a larger variety of webpages, we would

usually type in synonyms for particular search terms (in this case the word

‘tough’). This can be time consuming as individual searches have to be performed.

To prevent this, we use the tilde symbol (~). Placing this symbol before a

particular search term allows the Google search engine to give us a variety of

results. As seen in figure 6, searching for ‘Biology is ~tough’ gives results which

contain the sentences ‘Biology is hard’ and ‘Biology is difficult’, that essentially

have the same meaning as our query.

Problem 7: Searching for a particular file type.

Solution: Using the Google ‘filetype:’ feature.

Query: ‘Earthquake facts filetype:xls’ [fig.7]

Fig. 7 shows search results for

query no. 7, the user requires

facts organized in the form of

a table.

What’s happening:

When we search simply for earthquake facts, we get our results in various

formats such as .pdf, .doc, .html etc. However, a .pdf format may not display the

facts as clearly as, e.g. , a spreadsheet document. In order to get results that

specifically show the spreadsheet format, we add ‘filetype: xls ‘ to our query.

Problem 8: Converting units or currencies without physical use of a calculator or

physical calculation.

Solution: Use of Conversion feature from Google search engine.

Query: 1 GBP(British Pound) in USD (US Dollars), 24 in (inches) in ft (feet) both [

fig. 8].

Fig. 8 (above) conversion of pounds to

dollars; (below) conversion of inches to

feet.

What’s happening:

Conversion is made easy by using the names of units and currencies along with

numbers and entering them as search terms into the search box. Google search

engine immediately identifies the given format and displays conversion as shown

in figure 8. This is done when conversion through lengthy physical calculation is

not required.

Problem 9: Searching for similar webpages without searching for each site

individually

Solution: Using the ‘related:’ feature

Query: related: www.facebook.com [fig. 9].

Fig. 9 shows results that have are

similar to each other in function.

What’s happening:

When we use the ‘Related:’ function, we get webpages or websites that

essentially have a similar built or purpose. As shown in figure 9, websites related

to Facebook, a social networking site, include myspace, twitter, youtube and hi5.

All of these sites fulfill the purpose of social networking and thus are related to

each other in that respect. We can use the ‘related:’ function to verify and

validate same information from various sites.

Problem 10: Finding a site when you remember its URL address only partially

Solution: using ‘ inurl: ’ function

Query: ‘inurl:Android4.0’ [fig. 10 ].

Fig. 10 shows results for

‘inurl:android4.0’. Android 4.0 appears

in all the URL addresses listed.

What’s happening:

Using the ‘inurl:’ function, we limit the search results to only those webpages that

contain our keywords in their URL addresses. Such webpages according to

statistics contain more relevant information on our search terms when compared

to webpages that contain our search terms in their contents only.

As these 10 examples show, the Google search engine is more powerful than the

average search engine. Among other features of the Google search engine are:

1. ‘define: …’: definition of a search term is generated instead of using an

online or paperback dictionary for the purpose.

2. ‘+’: Used to perform a force search on all the search terms instead of

focusing on certain keywords.

3. ‘Weather’ : Entering this along with the name of a city and a country, gives

a weather forecast of that location.

4. ‘Time’ : using this along with the name of a city or country gives the local

time of that area.