1. G042 - Lecture 09 Commencing Task A Mr C Johnston ICT Teacher www.computechedu.co.uk

2. Session Objectives Understand what a search engine is and how they help us locate information on the world wide web, Know a range of different search techniques which can be used to get information from search engines, Use some basic techniques acquire some information for your investigation.

3. What Is A Search Engine Manual navigation of millions of web pages and thousands of newsgroups is impractical, A search engine is a catalogue of web pages, It stores details about site which searches can be carried out on, A search engine therefore is a user interface which allows you to search a huge database containing lists of web pages and newsgroups, Search Engines comprise of three main components: Sourcing the data Indexing and creating the database The search engine application

4. Search Engine Application Main user interface is written in HTML with a box for users to enter a search string into, When the search button is pressed the search string is processed by a computer programming language and a search is executed on the search engine database, The results are generated and displayed in a dynamic HTML page using a mixture of programming code and HTML. Machine With Internet Connection Search Engine Web server Search Engine Request Search Results Returned Database Queried Query Results Search Engine Database

5. Search Engine Facilities Standard search box allows you to enter phrase words Advance search facilities allows you to have more control over your searches by customising the search string using a user interface Create your own customised searches within the standard search box using Boolean operators – AND, OR, NOT

6. Selection of Search Engines There are a number of different search engines available – some better than others! Most allow you to carry out searches using the tips on the last slide, others however are more intelligent and you just enter a question and the engine attempts to answer it, Below is a list of common search engine: www.google.co.uk www.yahoo.co.uk www.msn.co.uk www.ask.co.uk www.lycos.co.uk www.excite.co.uk

7. The Task Using key words within the standard search box find websites which give you information to assist with your investigation HINT – you have already written down in your introduction what you are trying to find! Carry out similar searches in different search engines Take screen shot evidence clearly showing search terms and the results generated… Once you have carried out a variety of searches in different engines summarise your findings and evaluate the methods used - how you could improve your searches..

8. Evaluating Results Number of results Quality of results in terms of reliability, validity and bias, When thinking about websites consider: the URL, for example:.gov,.ac,.ed,.org,.co,.com,.sch endorsements, e.g. NgFL, the date of the last update, the author, advertisements, links to and from the website

9. Further Reading… Guide to Google searching http://www.google.com/support/websearch/?ctx=web Guide to searching on Yahoo http://help.yahoo.com/l/uk/yahoo/search/basics/ Guide to searching with Ask http://help.uk.ask.com/en/docs/about/help_central.shtml Guide to searching with MSN http://help.live.com/help.aspx?project=wl_searchv1&market=en- GB&querytype=keyword&query=redliub&tmt=&domain=search.live.com:80 http://help.live.com/help.aspx?project=wl_searchv1&market=en- GB&querytype=keyword&query=redliub&tmt=&domain=search.live.com:80 General searching tips http://www.bbctraining.com/pdfs/internet_res.pdf http://www.computechedu.co.uk/resources/agce/Unit03/lectures/Lec02Sear chEngines.ppt http://www.computechedu.co.uk/resources/agce/Unit03/lectures/Lec02Sear chEngines.ppt