Page 8 - Computing Book 8

Internet Search Techniques and e-Safety Class 8

Internet Search Techniques and e-Safety

Key Learning Points:

This chapter focuses on the use of search engines to extract the required information. The practical
component of this chapter allows students to use different search engines to extract information on
any topic by using appropriate “keywords”.

Search Engine:

A search engine is designed to search for information on the World Wide Web by using specified
keywords. The search results are usually presented in a list commonly called hits. The information
may consist of web pages, images, information and other types of files. Below are some of the most
common search engines:

1. www.google.com For generally searching for anything.

2. www.images.google.com For image searching.
3. www.scholar.google.com For educational and research type searches

4. www.books.google.com For online books search
5. www.yahoo.com For generally searching for anything.

6. www.duckduckgo.com For organic Searching.

How a Search Engine Works:

Internet search engines are special sites on the web that are designed to help people find
information stored in other sites. There are differences in the ways various search engines work, but
they all perform three basic tasks:
1. They search the Internet -- or select pieces of the Internet -- based on important words.
2. They keep an index of the words they find, and where they find them.
3. They allow users to look for words or combinations of words found in the index of words.
Early search engines held an index of a few hundred thousand pages and documents and received
maybe one or two thousand inquiries each day. Today, a top search engine will index hundreds of
millions of pages, and respond to tens of millions of queries per day. Google receives over 63,000
searches per second on any given day. That's the average figure of how many people use Google a
day, which translates into at least 2 trillion searches per year, 3.8 million searches per minute, 228
million searches per hour, and 5.6 billion searches per day.

The City School /Academics/Computing Curriculum/Class 8/2020-2021 Page 7 of 75