Post on 02-Jul-2015
description
COMPO2
Introduction to Information System
Information System
Is any combination of information Technology and people’s activities using that technology to support operations, management.
In other words, IS is frequently used to refer to the interaction between people, algorithmic processes, data and technology
Components of IS
1. Management Information System
It is a system that provides information needed to manage organizations efficiently and effectively.(resources such as technology, information and people)
2. Decision Support System
Is a computer based information system that supports business or organizational decisional activities.
DSS serves as the management, operations, and planning levels of an organization and help to make decisions which may be rapidly changing and not easily specified in advance.
DSS includes knowledge based systems.
(ex. Inventories, Comparative sales, projected revenues)
3. Executive Information System
Is a type of MIS intended to facilitate and support information and decision-making needs of senior executives.
Considered as specialized form of DSS.
4. Transaction Processing System
It collects, stores, modifies and retrieves transactions of an organization.
WEB or the WWW
It is a system of interlinked hypertext documents accessed via the internet.
With a web browser, one can view web pages that may contain text, images, videos and other multimedia and navigate between them via hyperlinks
**hypertext is a text displayed on a computer with references to other text that reader can immediately access usually by a mouse click
**hyperlink is a reference to a document that reader can directly follow or followed automatically. It points out the whole document or to specific element within a document.
(hypertext is a text with hyperlink)
Surfing the Web
Surfing is the term used to denote the navigating around different websites.
1. In order to surf the Web, you need a web browser, a software application for retrieving, presenting and traversing information resources on the WWW.
Popular web Browser
Internet explorer – 36.3%
Firefox – 24.1%
Chrome – 18.2%
Safari – 10.7%
Opera – 4.4%
Android – 1.7%
As of aug. 2011
Once you have a web browser, you must ensure that your internet connection are established well.
Then, you may now launch your web browser
Type the complete URL address of a site into the address bar of your web browser.
Then navigate it through hyperlinks and address bar.
Client VS server
Client is an application or system that accesses a service made available by the server whereas
Server is a computer program running to serve request of other programs – the client
They are connected via a network
Together they called
Client-server architecture
Website
A collection of interrelated web pages containing images, videos or other assets.
It is hosted on at least one web server, accessible via network such as internet through URL.
Components of website
HTML
- For the content
CSS
- For the design
Javascript
- For the interaction
PHP
- For the dynamic web pages
Web page
Is a document or information resource that is suitable for the WWW and can be accessed through a web browser.
It is composed of an HTML tags
URL
Uniform Resource Locator
Universal Resource Locator
It is a character string that specifies where a known resource is available on the internet and the mechanism for retrieving it.
Searching the web
It means the user will try to access their needed information through web
Web gives millions of results in just few seconds
User use different search engines for web searching
Popular Search Engine
Google 150 M Yahoo 137 M Bing 80 M ASK 60 M Teotama 9M Duck Duck Go 198K Entire Web 123K Blekko 120K Scrub the web 58K Gigablast 29K
Some ethical issues in web
Protection of intellectual property
Prevention of fraud
Protection of freedom of expression versus problems of defamation
Protection of privacy
control of spamming
What is HTML?
HTML stands for Hyper Text Markup Language
It is a language for describing web pages
It is not programming language, it is mark up language
Mark up language is a set of mark up tags
It uses mark up tags to describe web pages
It is invented by Tim Berners- Lee in 1989
Application needed in creating HTML
Internet Browser
HTML editor
A graphic program
HTML tags
These are the keywords surrounded by angle brackets like <html>
Usually tags come in pair like <b> and </b>
The first tag in a pair is the start tag, the second tag is the end
Start and end tags are also called opening tags and closing tags
HTML example
<html>
<head>
<title> hello </title></head>
<body>
Hello
</body>
</html>
Hello
Parts of HTML tag
<html> - tells the web browser on the type of the document
<head> - technical information about the document is stated
<title> - gives the document a name
<body> - where the actual documents are places
Basic formatting tags
<b> bold</b> - to make the text bold
<strong> </strong> - also for bold
<u> </u> - for underline
<i> </i> - for italic
<em> </em> - also for emphasis
<strike> </strike> - for strike through
<center> </center> - to align text in center
<tt> </tt> - for teletype text
<h1> </h1> to <h6> </h6>-
for heading
<br>
for breaking lines
<pre> </pre>
preformatted text
Preserves spacing
<sub></sub>
subscript
<sup></sup>
superscript
HTML elements
Html elements starts with a start tag / opening tag
Html elements starts with a end tag and closing tag
The element content is everything between the start and end tag
Some html elements have empty content
HTML comments
It makes html codes to make it more readable and understandable
It is ignored by the browser and are not displayed
<!---this is a comments ----->
Paragraph tags
HTML documents are divided into paragraphs
This is defined with <p> and </p>
it has one attribute which is align
Example : <p align = “right/center/left”> sample paragraph</p>