The document provides an introduction to search engines, defining them as software systems that enable users to find information on the web, with examples such as Google, Bing, and Yahoo. It details key components, including web crawlers, indexing, and algorithms, explaining how Google specifically operates through crawling, indexing, and serving search results. The document also includes tasks for analyzing search trends and content results, highlighting the importance of relevance and quality in search rankings.

1. What is a Search Engine?
Govt. College of Technology Tangi, Charsadda
By – Engr. Arshad Ali ( Assistant Professor Information Technology)

2. Introduction to Digital Marketing
Topics to be covered
1. Search Engine Definition
2. Examples of Search Engines
3. Key Components of a Search Engine
4. How Google Works

3. Definition
 Definition: A search engine is a software system
that enables users to search for information on the
World Wide Web (www).
 A software system is a collection of programs that
collectively performs a desired action … search the
information based on user’s query.

4. Examples of Search Engines
Examples: Google, Bing, Yahoo

5. Google
Founded: 1998
Market Share: Dominates the global search engine
market.
PageRank Algorithm: Ranks websites based on their
relevance, User Experience and quality.
Universal Search: Integrates various types of content,
including text, images, videos, news, and more.
Products: Google Search, Google Maps, Google
News, Gmail, Google docs, Google Sheets and more.

6. Bing
 Founded: 2009 by Microsoft
 Market Share: Second-largest search engine
globally.
 Image and Video Search: Offers advanced filtering
and high-quality results.
 Integration with Microsoft Services: Seamless
integration with Windows, Office, and Xbox.
 Products: Bing Search, Bing Maps, Bing News,
and more.

7. Yahoo
 Founded: 1994
 Market Share: Historically significant but now
smaller compared to Google and Bing.
 Yahoo Answers: A community-driven Q&A
platform.
 Yahoo Finance and News: Comprehensive finance
and news content.
 Products: Yahoo Search, Yahoo Mail, Yahoo
Finance, and more.

8. Key Components of a Search Engine
 Web Crawlers: Also known as spiders or bots, these
automatically browse the web and index content
 Indexing: Organizes the information gathered by crawlers
into a searchable database
 Algorithms: Complex formulas that determine the
relevance and ranking of pages
 User Interface: The front-end where users enter queries
and view results
 Search Results: The output, including links, descriptions,
and sometimes images, videos, or other media

9. How Search Engine Works?
 The main steps include Crawling, Indexing, Searching and
Ranking

10. How Search Engine Works?
Crawling Web Crawlers (Spiders/Bots)
Definition: Search engines use web crawlers (also known
as spiders or bots) to discover and scan new and updated
web pages.
Indexing Indexing Database
Searching Search Algorithms
Ranking Data relevancy, Content Quality, User experience

11. How Google Works?
 This base knowledge is necessary to fix common issues
related to indexing and Search Engine Optimization.
Google Search works in three stages
 Crawling: Google downloads text, images, and videos
from pages it found on the internet with automated
programs called crawlers, Googlebot, robot, bot.
 Indexing: Google analyzes the text, images, and video
files on the page, and stores the information in the
Google index, which is a large database.
 Serving search results: When a user searches on
Google, Google returns information that's relevant to the
user's query.

12. Google Crawling Process
 In the first stage to find new and updated pages
 This process is known as “URL Discovery”
 Pages become discovered once visited by crawling bots
 Pages may be discovered by following a link from known
pages to a new page
 “Sitemap or robot.txt” may be used to let google know
about your new/updated pages ( yet not indexed)
 A huge set of computers can crawl billion of pages on
internet

13. Google Indexing
 In the second stage the Google tries to find what the content is about
 indexing process is based onTags, title, alt-text and textual analysis
 It is found if the page is duplicate or canonical for the next stage ( Search
Results)
 All information collected about a page is stored in a database called
Google Index
 This database is stored on thousands of computers on internet

14. Serving Search Results
 In the third stage relevant and quality content are displayed in SERPs
 SERPs: Search Engine Results Pages
 Each time the user enters the query, the index is sorted out
 Content with high degree of relevancy and quality is provided in SERPs
 Ranking of any Web Page is determined by so many factors

15. Issues With Search Results
 Search Console might tell you that a page is indexed, but you
don't see it in search results. This might be because:
 The content on the page is irrelevant to users' queries
 The quality of the content is low
 Robots meta rules prevent serving

16. Issues With Search Results
 Search Console might tell you that a page is indexed, but you
don't see it in search results. This might be because:
 The content on the page is irrelevant to users' queries
 The quality of the content is low
 Robots meta rules prevent serving

17. Google Search Ranking Systems
 Google Search Ranking systems sort Google index consisting
of hundred of billion pages in a fraction of second
 The content on the page is irrelevant to users' queries
 The quality of the content is low
 Robots meta rules prevent serving

19. Task No. 2 (Marks: 50)
1. “Using Google Trends, compare the popularity of three different search terms of
your choice over the past five years. Analyze the data to identify any significant
trends, seasonal variations, and geographic differences.”
 Note: Submit it in Google classroom
2. "Conduct specific searches on Google and analyze the types of content that
appear in the results (websites, news, images, videos). Identify and discuss the
factors that may influence the ranking of these results, such as keywords, site
structure, and page authority."