CS177 Programming with Multimedia Objects

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CS177Programming with Multimedia Objects

• Week 1
• Recitation Slides

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Questions on Lectures
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Important Things to Remember

• Course Webpage
• http//www.cs.purdue.edu/homes/cs177/
• Lecture Recitation slides are posted there
• Projects will be posted there
• Contact details of all TAs is available there

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Computers

• What is a computer ?
• A device that receives, stores and processes
  information
• Why do we need them ?
• Computers are incredibly fast, accurate, and
  stupid humans are incredibly slow, inaccurate
  and brilliant together they are powerful beyond
  imagination
• Albert Einstein

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Types of Computers

• What are the different types of computers ?
• Desktop computers
• Supercomputers
• Palmtops (aka PDAs)
• Laptops
• What are the distinguishing features between them
  ?
• Speed
• Size
• Memory
• Peripherals
• Each type of computer has its own application e.g
  supercomputers perform computation intensive
  tasks, palmtops and laptops provide mobility to
  users

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Computer Specifications

• What are computer specs?
• The capabilities of a computer. For example, hard
  disk space, memory size, processor speed, etc.
• Contemporary desktop configurations include
• CPU Multi-core (dual-, quad-, eight-core)
• RAM 1-4 GB
• Hard drive 100 GB to 2 TB
• Graphics card 256 MB to 1 GB with a multi-core
  graphical processing unit (GPU)
• Optical drive Blu-ray disc, DVDRW, CDRW
• A lot of USB ports
• Legacy features such as floppy drives, zip
  drives, PS/2 ports, serial ports, etc. tend to
  disappear in newer systems
• Specs get better day by day because computer
  technology is evolving rapidly

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Hardware vs. Software

• What is hardware?
• The physical components of a computer (hard disk,
  processor, mouse, keyboard, monitor, etc).
• What is software?
• The programs that are written to make the
  computer do something interesting.
• An anonymous quote
• The easiest way to tell the difference between
  hardware and software is to kick it. If it hurts
  your toe, its hardware ?

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The von Neumann Architecture

• What are the 3 essential components of the von
  Neumann architecture?
• Input/Output devices Allow the user to interact
  with the computer.
• Memory Stores data and programs.
• Central Processing Unit (CPU) Performs
  instructions in programs to process information.
• Which of the three components was a major change?
• Storing programs in memory (before von Neumann
  only data was stored in memory)

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Central Processing Unit

• What is the CPU?
• It executes instructions in programs to perform
  specified tasks. In other words, it is the
  brain of the computer
• What unit is currently used to measure CPU speed?
• Gigahertz (GHz)
• What does a 2.3 GHz processor mean?
• The processor can execute roughly 2.3 billion
  instructions per second.

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Central Processing Unit Cont.

• What is an instruction?
• A very simple operation the CPU can perform (add
  two numbers together, move this data over here,
  check if this number is zero or not)
• How do computers do such complex stuff with such
  simple commands?
• Remember what Einstein said ?
• Computers are incredibly fast
• The speed of computing makes complex operations
  appear simple

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Memory

• What is memory?
• The place where the CPU stores and fetches data
  and instructions.
• How are the data and instructions stored?
• In binary (ones and zeros). Each digit is a
  bit.

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Memory Cont.

• What basic unit is used to represent memory
  capacity?
• The byte 8 bits (28 256 possible values)
• What does 2GB RAM mean?
• Roughly 2 Billion bytes of memory.
• How to compare RAMs with each other ?
• Faster read/write time, more space (i.e. bytes)

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Memory Cont.

• What types of memory are there?
• Main fast and expensive
• Secondary slower, but cheaper
• What are some examples of main memory?
• RAM, cache (memory that is saved for faster
  access the next time)
• What are some examples of secondary memory?
• Hard disk, CD-ROM, flash drive, floppy disk

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Memory Cont.

• What is the difference between permanent and
  volatile memory?
• Volatile memory is gone when the computer is
  turned off, while permanent memory stays around.
• What are some examples of volatile memory?
• RAM, cache (main memory)
• What are some examples of permanent memory?
• Hard disk, Compact Disk (CD), flash drive, floppy
  disk (secondary memory)

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Software

• What are programs?
• Sequence of instructions that, when executed, do
  something useful.
• What are some examples of programs?
• Microsoft Word, Wordpad (word processors)
• Internet Explorer, Mozilla Firefox (browsers)
• Windows Media Player, Winamp, RealPlayer (media
  players)
• World of Warcraft, The Sims, Halo (games)
• Gmail, Hotmail, Purdue Webmail (email)

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Operating Systems

• What is the operating systems main task?
• Controls and manages access to system resources
  by programs (memory, CPU, etc.)
• What are some examples of Operating Systems used
  today?
• Windows Vista, Linux, UNIX, Mac OS
• DOS (an old instruction based OS)
• How are they different?
• User-friendliness, services, stability, security

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The Internet WWW

• What is the Internet?
• The global interconnection between computers
  (network) that supports communication.
• What is the World Wide Web?
• An application of the Internet that allows
  interlinking of documents and resources.
• What are some other services available through
  the Internet?
• Email, Video Conferencing, Multiplayer Gaming

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The Internet WWW Cont.

• What is a protocol?
• The rules that govern communication between two
  or more computers on a network (e.g. the
  Internet)
• Protocols allow coordination between programs
  over the Internet
• For example, the web browser (Internet Explorer)
  and web server (www.google.com) communicate
  through the HTTP protocol

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Web Address

• What is a URL?
• Web pages require uniform names to locate and
  identify them uniquely
• There are 4 parts to a URL Protocol Name, Server
  Name, Directory Name, and File Name

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Web Address Cont.

• What if no file name is given?
• The server will look for a default file such as
  index.html
• What is no directory name is given?
• The server will look in the default directory

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Viewing Local HTML File Under Development

• a Web browser can be used to view pages stored on
  the same computer
• can go through the File menu to select the local
  page, or
• can enter the File location in the address box
  (without the http prefix)
• You should always preview your web page before
  uploading it to a server

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Next Week

• Labs will start next week
• Chapter 2 - HTML
• HTML basics
• Formatting text
• Images, hyperlinks, lists
• Tables

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Questions