The Internet is a distributed computer network. Its content is contained on the hard drives of millions
of computers which share a standard computer language to communicate with each other.
The content on the hard drives of these millions of computers can change at any time.
There is no central repository which keeps track of every single page of every single computer on
Instead we have Search Engines. These actively trawl the internet, reading and categorising web-sites and individual web pages, and indexing them into giant databases. All search engines work by cross-referencing your enquiry with the database of knowledge they have accumulated. Different search engines trawl and index in different ways and have different collections of the total content available online, so if you can't find what you are looking for with one try another.
We have to think about what we are looking for, not just haphazardly type words into the Google Search engine. We have to tell the computer just what we want. So think about what it is you want to find before just typing in any words.
Most database searching is based on the principles of Boolean logic. Boolean logic refers to the logical relationship among search terms, and is named after the British mathematician George Boole.
It is simple and consists of the three logical operators:
AND , OR, NOT (the AND is shown as +, the NOT is shown as - )
Which looks like this:
Search for dog AND cat
Search for dog OR cat
Search for dog NOT cat
Let's start with a search for Rugby Union, but we do NOT want to include the Citibank cup.
If we just type rugby union in the Google search box we will come up with literally hundreds of files from all over the world.
The search engine has actually given us all the files containing the separate words - rugby and also union.
We can avoid that and just get the files containing both words only by using quotation marks like this: "rugby union". Now we will only get files where both words are contained.
That is still far too many files, so let's narrow the search further to Australia. The easiest way to do this is to type in the search box: "rugby union", .au Note that I have put a comma after rugby union. This helps the search engine to narrow things down. Now we should only have files from Australia.
Now we have to discard all the files containing the word Citibank. So we type: "rugby union", .au -Citibank
Sometimes there will be a reference line to the NOT required information.
Now let's try something else.
We will find all the Florists in Port Macquarie.
In the search box type: "Port Macquarie", .au +florists
We should come up with florists in and around Port Macquarie.
Let's try it for London . type in: "London", .uk +florists
Now you can see how you have to think about what you want to search for.
You can use the same method to get pictures or images.
Type in: "Port Macquarie", .au +images
We should get all the pages for Port Macquarie containing the word images.
We can also type in a specific sentence. The search engine will go and search for anything containing that sentence.
Type in: "How does Quinine stop people from getting malaria but is it by stopping the mosquitoes or the malaria?"
You will be surprised how your search has been narrowed to just those subjects.
Prepared by - Peggy