Transcript Introduction to Computers and the Internetx

Introduction to
Computers and the Internet
Information Technology Department
Bryar Hassan (BSc & MSc Eng.)
[email protected]
Contents
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What is a Computer?
Evolution of the Internet and WWW
World Wide Web Consortium (W3C)
Web 2.0
A Communication Model
Networking
The Internet
Software Technologies
Internet Technology – First Year
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What is a Computer?
• Computer
– Device capable of
• Performing computations
• Making logical decisions
– Works billions of times faster than human beings
– Fastest supercomputers today
– Perform hundreds of billions of additions per second
Internet Technology – First Year
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What is a Computer? (Cont.)
• Programs
– Sets of instructions that process data
– Guide computer through orderly sets of actions specified by computer
programmers
• Computer system
– Comprised of various hardware devices
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Keyboard
Screen
Disks
Memory
DVD drives
Processing Units
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Evolution of the Internet and WWW
• ARPANET
– Implemented in late 1960’s by ARPA (Advanced Research Projects Agency of
DOD)
– Networked computer systems of a dozen universities and institutions with
56KB communications lines
– Grandparent of today’s Internet
– Intended to allow computers to be shared
– Became clear that key benefit was allowing fast communication between
researchers – electronic-mail (email)
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Evolution of the Internet and WWW
• ARPANET’s Goal
– Allow multiple users to send and receive info at same time
– Network operated packet switching technique
• Digital data sent in small packages called packets
• Packets contained data, address info, error-control info and sequencing info
• Greatly reduced transmission costs of dedicated communications lines
– Network designed to be operated without centralized control
• If portion of network fails, remaining portions still able to route packets
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Evolution of the Internet and WWW
• Transmission Control Protocol (TCP)
– Name of protocols for communicating over ARPAnet
– Ensured that messages were properly routed and that they arrived intact
• Organizations implemented own networks
– Used both for intra-organization and communication
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Evolution of the Internet and WWW
• Huge variety of networking hardware and software appeared
– ARPA achieved inter-communication between all platforms with development
of the IP
• Internetworking Protocol
• Current architecture of Internet
– Combined set of protocols called TCP/IP
• The Internet
– Limited to universities and research institutions
– Military became big user
– Next, government decided to access Internet for commercial purposes
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World Wide Web Consortium (W3C)
• W3C Founded in 1994 by Tim Berners-Lee
– Homepage at www.w3.org
• Goals
– Internet universally accessible
– Standardization
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Web 2.0
• The term Web 2.0 was coined by Dale Dougherty
– Web 2.0 definition = companies use the web as a platform to create
collaborative, community-based sites (e.g., social networking sites, blogs,
wikis, etc.).
• Web 1.0 (1990s and early 2000s) focused on a small number of
companies and advertisers producing content for users to access
• Web 2.0 involves the
– Web 1.0 is as a lecture,
– Web 2.0 is a conversation
• Websites like MySpace , Facebook , Flickr , YouTube, eBay and
Wikipedia , users create the content, companies provide the
platforms.
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A Communication Model
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The Key Elements of this Model
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Source: generates data to be transmitted
Transmitter: converts data into transmittable signals
Transmission System: carries data from source to destination
Receiver: converts received signal into data
Destination: takes incoming data
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Networking
• Growth of number and power of computers is driving need for
interconnection
• Rapid Integration of voice, data, image, and video technologies
• Networking
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The Internet
• Internet evolved form ARPANET
– First operational packet switching network
– Applied to tactical radio and satellite nets also
– Led to standardized TCP/IP protocolsDevelop an understanding of various
internet applications
• Describe the basics of how internet works? Internet protocol IP
address assignment
• Explain the importance of websites and discuss ways to design a
basic website using HTML for personal use;
• Explain the use of webservers and cloud computing
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Internet Elements
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Internet Architecture
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Software Technologies
• Mark-up Languages
– HTML
– XML
• Dynamic Scripting Languages
– JSP
– PHP
– ASP.Net
• Other Scripting Languages
– JavaScript
– VB Script
– AJAX
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Software Technologies
• Programming Languages
– Machine languages
– Assembly languages
– High-level languages, such as Java, C++, and C#
• Web Servers
– Apache
– IIS
• Databases
– MySQL
– MS SQL Server
– Oracle
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