Sunday 26 June 2011

chapter 9

Modulation
Demodulation
Bandwidth
TCP/IP
Node
Client
Server
Network Operating Systems
Network Administrator






  • Modulation
Is a process of inflection high-frequency periodic waveform,in music it inflect the volume,pitch and sort to enable the signal to transport all the information in the modulation signal to a particular destination.

  • Demodulation
Is a process to extracting the original content signal from a modulated signal.Commonly used in connection that relate to radio receivers and modem.

  • Bandwith
Is a rate or amount of data that can be transfer in one time.
Usually expressed in bits/second,and also bytes/second.
It is really important for i/o devices.

  • TCP/IP
Is a short term for Transmission Control Protocol/Internet Protocol.
It's a set of general guidelines that is used to provide specific networking protocols that enables communicating with the network.
It has a variety types of communication services between computers.

  • Node
Node is a connection point or processing location.
It is different depends on the protocol layered and the networks.it can be either computer or other devices such as printers.Each node has it own unique network address.It's also can be use to recieve,send and forward informations over a communication channel.

  • Client 
Is an application which access remote service on other computer.
usually applied to a device that cannot stand by their own and need a connection to a remote server to run.


  • Server
Is a device on a network that work to manage the resources .
There are a lot of different type server:
File server:a computer that is used to storing data.can be use by any user to store file to the server.
Printer server:a computer that manage one or more printers.
base server:a computer which manage other computers in the same network.

  • Network Operating System
NOS which is an operating system that has a special function to connect computers and devices to a local-area network  (LAN).
It enable the server to manage user,security,groups,data,application and also other functions.

  • Network administrator
Is the person who is responsible to manage the maintenance of the computer hardware and software.
Network admin work in an situation which is not involving direct user support.
It's more focuses on the integrity of the workers,server deployment,and security
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Secondary Storage

Disk Caching
File compression
File Decompression
Internet Hard Drive
Optical Disk Drive
Solid-state Storage




  • Disk Caching
IS a part of RAM which is used to enhance the speed to access data on a disk.It works by storing all the frequent access data in the RAM cache.This will increase the performance of the cache.

  • File Compression
Is a process which the data is reduced than the original.Reduced the uses of memory space in the hard disk and etc.
Usually used to make data transfer faster.The user that want to use the data need to decompress the data first using related software.

  • File Decompression
Is the reverse process of compressing file.It decoding what is in the data.
Using software such as 7- zip program,user can open the date that have been compressed.

  • Internet Hard Drive
User can used internet hard drive to store data.The data can be access as long as user have internet access using any computer.
The drawbacks is ,it may take a longer time to upload the data,larger file will take longer time duration.

  • Optical Disk Drive
a storage medium which is used to read the data which is written by lasers.It has a large storing capacity up to 6 gigabytes.Most of optical drives can read numbers of formats such as CD-ROM ,CD-R and etc.

  • Solid-state Storage
SSD is a storage device that has no moving parts.Contain DRAM or EEPROM ,a CPU.battery card and a memory bus board.It providing faster access because it have their own CPU to maneage the data storage.


Input and Output

ergonomic keyboard
ink jet printer
laser printer
magnetic ink character
optical character recognition
optical mark recognotion


  • Ergonomic Keyboard
Is a keyboard which have 2 separated part with a V shape.
Design to reduced the muscle pain and less stress on the user hands.
Has two different desingn,fixed and separated.

  • Ink Jet printer
Is one type of printer that people use the most.Use ink to create a digital image on paper.
Have a wide range from small , orlarge for professionla use and different prices.


  • Laser Printer
Is a printer that used laser to print image which produces high quality result.
Range from 300 dpi at the low end at 1200 or 2400 dpi at the high end.


  • Magnetic ink character
is a character recognition technology that enable computers read the information that can also easily read by human.Mainly used in banking,because machine can read a magnetic-ink with a greater accuracy.

  • optical character recognition
Known as OCR,it involves reading text such as handwritten,printed text and typewritten into a form that can be manipulated by computer.Usually used to convert things such as book and documents and then edit it using word processor.


  • optical mark recognotion
Known a OMR,the functions of optical mark recognition is  extracting data from marks fields on a printed forms.OMR technology scans a printed form and reads predefined positions and records where marks are made on the form.

Monday 6 June 2011

RAM or known as random access memory,a type of computer data storage that takes form of the intergrated circuits that can be accessed randomly,commonly associated with volatile types of memory such as DAM memory modules,where it will store information if the power is off.


Cache: is a computer component that stores data transparently ,so that any request for the stored data can be access faster.data stored in cache might be computed earlier or duplicates of original vaalues that are stored elsewehere,cacahes are relatively small,so it is cost efficient.








Read only memory(ROM) is a storage medium used in computer and electronic devices which the data is already prerecorded.Different from the main memory(RAM),itholds it own data@contents even when the computer is turned off.The data stored in ROM can be modified in slowly speed or with difficulty,so the main purpose of ROM is it mainly used to distribute firmware.




Flash memory:
is a type of computer storage chip that is widely used,it is a memory that maintains stored information,it can be electrically erased and reprogrammed.it is used in memory card, USB flashdrivers,MP3 players and solid-state drivers for general storage.It cost far less compared to byte-programmable EEPROM .





Graphic Card
Graphic card is a part of hardware that is used to rendering the image on the compute'rs monitor or a display screen.this card usually offer added function,usually has a small amount of embedded memory and takes some of the main memory(RAM) ,it reduce the RAM available.




Sound Card:
Sound card or audio card is a an internal computer expansion card that stored input and output of audio signals.
also applied to external audio interface which use software to generate sound ,it is also providing the audio component for multimedia application.






Network Interface Card:
Is a hardware component that is used to connects a computer to a computer network.Usually implemented on expension card,then plug into a computer bus.






Plug and Play:
Is the ability to automatically configure expansion boards and other devices by a computer system it discover the hardware in the system,without need for a physical configuration.






Universal Serial Bus Port (USB):
is an external bus port which is used to establish communication between devices and host controller,which is effectively replaced earlier interfaces for example serial and parallel ports.
It can connect to com[puter peripherals such mice,modem,keyboard and also supports plug and play and hot plugging.






Serial Port:
Is a port,serial communication physical interface through which the information transfers in or out which only one bit is transmitted at a time.hardware more or less compliant to the RS-232 standard, intended to interface with  or communication device and modem.






Parallel port:
parallel communication physical interface it is an interface that is found in computers for connecting a wide range of peripherals.also known as the printer port or centronics port.






Firewire Port:
Is a form of serial port that transfer data with high speed from one device to another by using firewire technology.
it has the capability to interact with numbers of devices,it has lower implementation cost and more adaptable cabling system.




Ethernet Port:
Is a frame-based computer networking technologies,for local area networks (LAN),its involved a lot of wiring signaling standards for the physical layer of the standard networking model .
Also called as jacks or sockets.




High Definition Multimedia Interface Port:
Is an audio or video interface that is used to transmit uncompressed digital data,is an alternative to analog standards,support single cable,uncompressed  PC or TV  video format.













Wednesday 25 May 2011

System Unit

  • RAM
  • Cache
  • ROM
  • Flash Memory

  • Graphic card
  • Sound Card
  • Network Interface Card
  • Plug and Play


  • Universal Serial Bus Port(USB)
  • Serial Port
  • Parellel Port
  • Firewire port
  • Ethernet Port
  • High Definition Multimedia Interface Port

Wednesday 4 May 2011

Basic and Specialized application software

  • Graphical User Interface(GUI)
Graphical User Interface(GUI) is a user interface that represent directions,programs,and files with images and spatial relations.it add visual elements on the screen.
In the typical GUI, instead of laboriously typing commands at a prompt to tell the computer what to do, the user can simply choose commands by activating or manipulating the pictures
  • Word Processor
word processor or document preparation system used for composition editing,formatting and printing. The main usage of word processor is its ability to make changes easily, such as correcting spelling, changing margins, or adding, deleting, and relocating entire blocks of text.Once the document created, it can be printed quickly and accurately and saved for later modifications.
  • Spreadsheet
Spreadsheet is a computer application manipulates numerical and string data in rows and columns of cells. It defines how the the cell content is is calculated from other cells each time any content is updated.Several spreadsheet support three-dimensional matrices and cyclic references that lead to iterative calculation.



  •  DBMS 





DBMS is a database program. Technically , it is a software system that uses a standard method of retrieving,cataloging, and running queries on data.It is a programs that allow organization place their database in the hands of database administrator. It also allows different user application programs to easily access the same database
    • Utility Suite
    sutility suites is a software that analyze,configure ,optimize and maintain the computer.It focus on the computer infrastructure operates and utility suites is technical based and targeted to people who have advanced knowledge in in computer.Highly specialized and it is designed to run single task or small range task.

      • Web authoring
      A software that is used to develop a web sites in a desktop publishing format.It will generate the HTML code for the web pages layout based on the user custom design.Commonly the user can edit their web page in terms of graphical design and the HTML code.




      • Audio Editing Software
      Is an application that is used for the audio editing.The main software of the audio editing software is the digital audio workstation.These are some of the functions of the audio editing software:




      1. Edit the start time, stop time, and duration of any sound on the audio timeline.
      2. Mix multiple sound sources/tracks, combine them at various volume levels and pan from channel to channel to one or more output tracks



      • Bitmap Image
      Bitmap is a type of file formats that is used to store digital images in computerized form.
      bitmap is literally a map of bits that form a particular images when rendered to a display.Bitmap image is used in many Graphical User Interface (GUI) for their built-in graphic subsystem.Because bitmaps store many information in the highest resolutions, they make very beautiful images. 
      • Desktop Publishing Program
      Desktop publishing(DPT) is a tool for user to create publication documents on their computer output and distribution publishing.
      It's commonly referred to page layout but  the skills and software are not limited to paper and book publishing only,it's also used for create graphics for a lot of purpose.

      • HTML editor.
      HTML editor is a software that used to create web pages,Also known as an authoring tool, an HTML editor is a software program that inserts HTML  code as you create a HTML file. Some of the  editors will provide a word processing GUI enabling users to create HTML documents without knowing any HTML code.

      • Image  editor
      Image editor is a software that is used to altering images,converting the graphic formats.User can do such things like photo retouching,editing illustration and modify photographs.Image editors usually enable editing images with only bitmapped images such as GIFs, JPEGs and BMPs; however, some editors support both bitmaps and illustration.

      • Multimedia
      Multimedia refers to a lot of things,multimedia is the integration of multiple forms of media.Multimedia includes the combination of audio,video,text,images,animation,and interactivity.
      Multimedia is commonly recorded and played, displayed or accessed by  processing devices, such as computerized and electronic devices, but can also be part of a live performance.

      • Vector image
       Vector image is based on mathematical equations,vector graphics are comprised of paths, which are defined by a start and end point, along with other points, curves, and angles along the way,that represent images in computer graphics.Because vector-based images are not made up of a specific number of dots, they can be scaled to a larger size and not lose any image quality.

      Wednesday 27 April 2011

      Basic and specialized applicatiion software

      • Graphical User Interface(GUI)
      • Word processor
      • Spreadsheet
      • DBMS
      • Utility suites
      • Web authoring
      • Audio Editing Software
      • Bitmap image
      • Desktop Publishing Program
      • HTML editor
      • image editor
      • Multimedia
      • Vector image