1. AO3 – Investigate how Search
Engines Work
 Unit 2: Collaborative Working

2. Individual Task
• You will be working individually to
complete the work for this Assessment
Objective (although you will need your
groups assistant to collect examples).
Unit 2: Collaborative Working

3. Different Types of Search Engine
• Many different types but we’re going to
focus on four:
– Web Crawlers
– Directories
– Meta-search Engines
– Children’s Search Engines
Unit 2: Collaborative Working

4. Web Crawlers
• Sometimes known as web
spider, bot, crawler or automatic
indexer.
• Scans through Internet pages to create
an index of data it’s looking for.
• Web Crawler Search Engines:
– Google
– Yahoo Unit 2: Collaborative Working

5. Directories
• Directory-based search engines use
human editors.
• Search results should be more useful.
• Directory Search Engines:
– DMOZ
– Yahoo Directory
– UK Directory
Unit 2: Collaborative Working

6. Meta-search Engines
• Send your search term to databases of
web pages maintained by search engine
companies.
• Results returned from all the search
engines queried.
• Meta-search Engines:
– Clusty
– Dogpile
Unit 2: Collaborative Working

7. Children’s Search Engines
• Editors to ensure list of sites will be useful and
suitable for children.
• Automatic filtering so adult sites do not appear.
• Children’s Search Engines:
– Ask Kids
– CBBC
– Kids Online (KOL)
– Kids Click
Unit 2: Collaborative Working

8. Search Techniques
• Keywords
• Quotes
• Boolean Operators
• Wildcards
• Advanced Search Options
Unit 2: Collaborative Working

9. Keywords
• Example Keyword Search:
strawberry ice cream
– Displays all websites with the words
“strawberry” and “ice” and “cream”
somewhere on the page (not necessarily
together)
– Not always very accurate
Unit 2: Collaborative Working

10. Quotes
• Example Quote Search:
“strawberry ice cream”
– Displays all websites with the phrase
“strawberry ice cream” on the page.
– Much more accurate way of searching.
Unit 2: Collaborative Working

11. Boolean Operators
• AND(+), OR, NOT(-), NEAR
• Example of Boolean Operators:
“ice cream” +strawberry -chocolate
– Displays all websites with the phrase “ice
cream” on the page AND the word
“strawberry” but NOT “chocolate”.
Unit 2: Collaborative Working

12. Wildcards
• * or ? = wildcard symbols
• Example:
*bert
– Would display all websites with the words
“Albert”, “Dilbert” etc.
– Not supported in modern search
engines anymore.
Unit 2: Collaborative Working

13. Advanced Search Options
• Most search engines have an
advanced search feature.
• Very customisable. You can select:
– Exact phrases
– Words to include/leave out
– Country
– Language
– Website
Unit 2: Collaborative Working

14. AO3 Portfolio Evidence
 Describe the main features of each of the four
types of search engine.
 Give at least one example of each one.
 Explain the appropriate use of each of the five
search techniques and use them in each of
the four types of search engine to find out
information for your part of the group project.
 Compare the results of using the different
techniques in different types of search engine.
Unit 2: Collaborative Working