The Internet

October 30, 2007

The Internet

• URL’s

• Search Engines

• Boolean Operators

• Internet Searches

• Scavenger Hunt

URL’s

• The address of a web page

• URL =

• = Uniform Resource Identifiers– Universal Resource Identifiers– Uniform Resource Locators

• 31 billion web pages with URL names!!!

URL’s

• 6 Examples

http://www.whitehouse.gov

http://forums.about.com/ab-guitar/messages/?msg=61981

https://www.nbnzco.nz/login.asp

ftp://ftp.download.com/publictelnet.//freenet.ecn.ca

gopher://205.17.0.108

URL’s

• Some general rules:• Never has any spaces in it• For the most part it is all lower case• Not the same as an email address• Always starts with protocol prefix

• Eg. http:// - most browsers will type that for you

• Other internet protocols• Eg. ftp:// gopher:// telnet:// irc://

ANATOMY of a URL

ANATOMY of a URL

ANATOMY of a URL

Search Engines

3 kinds of search engines

1. Crawler Based

3. Hybrids

2. Human Powered Directories

Crawler Based Search Engines

• Eg. Google• Create listings automatically

• Crawl or spider web produce list that we go through

• These engines will eventually find any changes you make to your site and will update the index accordingly

Human Powered Directories

• Eg. Open Directory• You submit a short description to the

directory for your entire site• Editors can also write a summary for a site

they view as well

• When you search a directory you are only searching the descriptions, NOT the sites

Hybrid Search Engines

• Combine the best of both worlds!

• Eg. MSN search

• Usually these favour Crawler or Human, they’re never ½ and ½.

• MSN favours human powered over crawler

How do Search Engines Work?

• 3 Elements1. Spider (aka crawler)

Visits web page, reads it and goes to other pages that are linked on the site

Site was “spidered”

Returns every month or two to check for any changes

How do Search Engines Work?

1. Spider to Index

Spider Index or Catalog

A site will not turn up in a search until it has been indexed or catalogued.

How do Search Engines Work?

1. Search engine software

Sifts through the index to find any matches to a search

Takes any matches and ranks them in order of relevance for you

Searching the Net

• What do you type into the Search bar so you will find what you’re looking for???

Searching the Net

Boolean Operators

Searching the Net

• The use of words to show the relationship between two items

AND

OR

NOT

Searching the Net

• Can also use “” (Quotes – not smiley)

• Quotes will _______ your search because the words need to show up side by side

• Quotes also make your search more direct and you tend to get better results!

Searching the Net

• Using + and – signs also helps your search!

• + tells the search engine which keyword you think is most important

• + must have a space in front of it and must be attached to the word it relates to

• - removes words that you do not want included in your search results