Introduction to Computer and Computer Networking: Part I

1
Introduction to Computer and Computer Networking
Part I

• Xiangming Mu
• 9/16/2004

2
What Is a Computer and What Does It Do?

• A computer is a programmable electronic device
  that accepts data and performs operations on that
  data.
• Inputentering data into the computer.
• Processingperforming operations on the data.
• Outputpresenting the results.
• Storagesaving data, programs, or output for
  future use.

3
Computers to Fit Every Need

• Five basic categories
• Mobile devices
• Personal computers
• Midrange servers
• Mainframe computers
• Supercomputers

4
Operating Systems

• System software acts as a mediator between
  application programs and the hardware resources
  of the computer system.
• Application software provides the tools to
  perform particular tasks on a PC, such as writing
  a letter, processing orders, playing games,
  composing and e-mail, and so forth.
• Most programs use a graphical user interface
  (GUI).
• The most common operating systems for PCs today
  is Microsoft Windows.
• Other GUI operating systems are Mac OS and Linux.

5
(No Transcript)
6
And more
7
Data and Program Representation

• Computers today are mostly digital
  computersdevices that can only understand two
  states.
• The two states of a digital computer are
  typically represented by 0s and 1s that is, in
  binary form.
• Computers do all processing and communications in
  binary form, so natural-language input and output
  are translated to and from binary by the computer.

8
(No Transcript)
9
Coding Systems for Text-Based Data

• ASCII and EBCDIC
• Fixed-length codes that can represent any single
  character of data as a string of eight bits.
• Unicode
• A longer (32 bits per character is common) code
  that can be used to represent text-based data in
  virtually any written language.
• Graphics dataoften stored as a bitmap which the
  color to be displayed at each pixel stored in
  binary form.
• Audio datawaveform audio is common MP3
  compression makes audio files much smaller.
• Video datarequires a great deal of storage
  space, but can be compressed.

10
Inside the System Unit

• The system unit of a PC is the case that houses
  processing hardware and other hardware.
• All of the hardware contained within the system
  unit is connected to the system board or
  motherboard.
• The CPU (central processing unit) does the vast
  majority of processing for a computer.

• Buses are electronic paths that data travels
  around on a computer system.
• RAM (random access memory) is the computers main
  memory and is used to temporarily storage
  programs and data with which it is working.
• Expansion cards can be inserted into expansion
  slots on the motherboard.
• Some external devices can be plugged into
  existing USB or FireWire ports without adding
  another expansion card.

11
Inside the System Unit

• The system unit of a PC is the case that houses
  processing hardware and other hardware.
• All of the hardware contained within the system
  unit is connected to the system board or
  motherboard.
• The CPU (central processing unit) does the vast
  majority of processing for a computer.

• Buses are electronic paths that data travels
  around on a computer system.
• RAM (random access memory) is the computers main
  memory and is used to temporarily storage
  programs and data with which it is working.
• Expansion cards can be inserted into expansion
  slots on the motherboard.
• Some external devices can be plugged into
  existing USB or FireWire ports without adding
  another expansion card.

12
Storage

• Magnetic disk storage systems
• Optical disc storage systems
• Other types of storage, such as flash memory,
  magnetic tape, remote storage, and smart cards

13
(No Transcript)
14
(No Transcript)
15
Input

• Input devices convert data from the user into a
  form understood by the computer.

16
Output

• Output devices convert the processed 0s and 1s
  into a form that the user can understand.
• Hard copypermanently recorded, such as on paper.
• Soft copytemporarily recorded, such as on a
  computer screen.

17
Computer Networks and the Internet

• A computer network links computers together so
  that users can share hardware, software, and
  data, as well as electronically communicate with
  each other.
• Network servers manage resources on a network.
• Clients are computers on the network that access
  resources via the network server.

18
What Is a Browser?

• A Web browser is a program used to view Web
  pages.
• Common browsers
• Microsoft Internet Explorer
• Netscape Navigator
• MSN Explorer
• Opera
• Wireless phones and other small devices use
  microbrowsers.

19
Internet Addresses

• An Internet address identifies a resource
  available through the Internet, such as a person,
  computer, or Web page.
• IP addresses (e.g. 207.46.134.222) and domain
  names (e.g. microsoft.com) identify computers
  available through the Internet.
• URLs (e.g. www.course.com) identify a Web page on
  the Internet.
• E-mail addresses (e.g. jsmith_at_course.com)
  identify a person on the Internet.