2. Starter Activity: Search Engine Secrets
Why do you think search engine companies like
Google are secretive about how their search
engine works?
Search Engines
3. In this lesson you will learn about how search
engines work and how they rank pages. You will
check the page ranks of web pages and create an
annotated diagram to explain how they are ranked.
Lesson
Objectives
Understand how a search engine works
Understand the different jobs of a search engine
Be able to describe how the PageRank algorithm works
Be able to check the PageRank of a page
Search Engines
4. Search Engines
•A search engine is a set of programs which are used
to search for information in a database
•There are over 250 search engines in the world
•They help people organise and display information
in a way that makes it easy to access
•As well as providing a website address they can
locate reviews and compare prices
Search Engines
5. Task 16: Search Engine Montage
Using individual images create a collage of search
engine logos.
Search Engines
6. Task 17: Ask Vs Yahoo
Using the two search engines above find out the
meaning of the word: “imbroglio”.
Discuss with your elbow partner which search
engine you prefer out of the two and why.
Search Engines
7. Watch the How Search Works video, this will
introduce you to how search engines work.
Search Engines
8. Working of Search Engines
There are three main jobs of a search engine:
1.Crawling – a process of going from web page to
web page via the links to seek out new content,
including updates to files and web pages.
2.Indexing – the programs index the information,
pulling out specific keywords to categorize it. The
data is stored in an online index database.
3.Searching – the engine examines its index and
provides a listing of best-matching webpages.
Search Engines
9. Search Engines Algorithms
Search engine algorithms are unique to every
search engine. There are some common things:
1.Relevancy – check for keywords on webpages
that are in your search
2.Individual Factors – the number of pages and the
frequency that a search engines indexes
3.Off- Page Factors – number of times a link on a
webpage has been clicked to visit another
webpage
Search Engines
10. Google Search Engine
•Created by Larry Page and Sergey Brin
•Founded September 4, 1998
•Most popular search engine
Search Engines
11. Google - PageRank Algorithm
1.Used to determine a page's importance
2.Important pages receive a higher PageRank
3.PageRank It is measured from 0 -10
4.The higher the PageRank the higher up the
webpage will be in the search results
5.PageRank is based on backlinks
6.The more quality backlinks the higher google
PageRank
Search Engines
12. Page Rank Algorithm Compared to Social Networks
People have links to people. If you have links to
famous people and they have link backs to you,
your page rank will be high!
Search Engines
13. Task 18: PageRank Check
1.Go to: http://www.prchecker.info
2.Click on the ‘Check Page Rank’
3.Check the PageRank for:
www.amazon.co.uk
www.argos.co.uk
www.tesco.co.uk
4. Which web page has the highest page rank
Search Engines
14. Task 19: PageRank Illustration
Create a diagram like the example below to
illustrate how PageRank works then annotate your
diagram to explain how the algorithm works.
Search Engines
15. Plenary: Brain Dump
Brian Dump what you now know about search
engines and the PageRank algorithm.
Search Engines
16. Keywords
Understand how a search engines work
Understand the different jobs of a search engine
Be able to describe how the PageRank algorithm works
Be able to check the PageRank of a page
Objectives
Search Engines
Backlink
PageRank
Algorithm
Searching
Crawling
Indexing
Database
Search Engines
