Communication and Network

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




Modulation

  • also known as continuous wave modulation
  • the addition of information (or the signal) to an electronic or optical signal carrier
  • can be applied to direct current (mainly by turning it on and off), to alternating current, and to optical signals
  • examples of modulation methods are Amplitude modulation (AM), Frequency modulation (FM), Phase modulation (PM)
  • to encode both digital and analog information in a binary way
Demodulation
  • the process of recovering the audio-frequency signal from the modulated wave is known as demodulation or detection
  • used in connection with radio receivers
  • Modulation is the addition of information (or the signal) to an electronic or optical signal carrier
  • can be applied to direct current (mainly by turning it on and off), to alternating current, and to optical signals
  • used in amateur radio, modern computers
  • examples of modulation methods are Amplitude modulation (AM), Frequency modulation (FM), Phase modulation (PM)
Bandwidth
  • also known as network bandwith, data bandwith, or digital andwith
  • is a bit rate or net bit rate(also known as peak bit rate, information rate or physical layer useful bit rate)
  • measure of a logical or physical communication path in a digital communication system
  • measure the maximum throughput of a computer network

TCP/IP
  • also known as Transmission Control Protocol/Internet Protocol
  • is a description framework for computer network protocol
  • is a set of general design guidelines and implementations of specific networking protocols to enable computers to communicate over a network 
  • used to connect hosts on the Internet 
Node
  • is a connection point
  • has programmed or engineered capability to recognize and process or forward transmissions to other nodes
  • can be a computer or some other device, such as a printer
Client
  • is an appication or system that accesses a remote service on another computer system 
  • not capable of running their own stand-alone programs, but could interact with remote computers via a network
  • is the requesting program or user in a client or server relationship

Server
  • a computer program running to serve the needs or requests of other programs which may or may not be running on the same computer.
  • a physical computer dedicated to running one or more such services, to serve the needs of programs running on other computers on the same network.
  • a software/hardware system (i.e. a software service running on a dedicated computer) such as a database server, file server, mail server or print server 

Network Operating Systems
  • also known as NOS or Dialoguer
  • runs on a server and enables the server to manage data, users, groups, security, applications, and other networking functions
  • allow shared file and printer access among multiple computers in a network
  • Secure access to a network
  • Back up data and make sure it's always available
  • Monitor the status and functionality of network elements
Network Administrator

  • also known as network admin
  • is the person responsible for the maintenance of computer ardware and software that comprises a computer network
  • their jobs include deploying, configuring, maintaining and developing active network equipment
  • support personnel that only work on break/fix issues that could not be resolved
  • manages a local area communications network (LAN) or wide area network (WAN) for an organization

Secondary Storage

  • Disk Caching
  • Gile Compression
  • File Decompression
  • Internet Hard Drive
  • Optical Disc Drive
  • Solid-State Storage
Disk Caching
  • is a mechanism for improving the time it takes to read from or write to a hard disk 
  • included as part of the hard disk
  • can also be a specified portion of random access memory(RAM)
  • holds data that has recently been read and, in some cases, adjacent data areas that are likely to be accessed next



File Compression
  • also know as Data Compression
  • to encode data before sending it to another place
  • commonly used when sending a file from one computer to another over a connection that has limited bandwidth
  • makes the file smaller and, therefore, the sending of the file is faster


File Decompression
  • reverse of  file compression-decoding of compressed data to restore the unique data


Internet Hard Drive
  • to access user's computer files such as pictures, documents, music, videos, etc. from any computer, as long as that computer has access to the Internet
  • unlike local hard drive, an internet hard drive provides unlimited disk space
  • lower risk to loose documents

Optical Disc Drive
  • also known as ODD
  • uses laser light or electromagnetic waves to read the data from a disc
  • used in computers to read software and consumer media distributed in disc form, and to record discs for archival and data exchange

Solid-State Storage
  • also known as SSD
  • is a data storage device that uses solid-state memory to store data providing access in the same manner of a traditional hard disk drive
  • it contains no mechanical parts, everything is done electronically
  • data transfer at a much higher speed

Input and Output

  • Ergonomic Keyboard
  • Ink-Jet Printer
  • Laser Printer
  • Magnetic-Ink Printer
  • Optical-Character Recognition
  • Optical-Mark Recognition

Ergonomic Keyboard 


  • computer keyboard that separates the keys into two halves shaped like a wide "V"
  • some have a fixed layout, while others are movable
  • puts less stress on the hands and wrist and winds up being comfortable platform for typing, for most people.
  • designed to to relieve sometimes painful conditions, minimize muscle strain and a host of related problems




Ink-Jet Printer


  • forms an image by using electromagnetic fields to guide electrically charged ink streams onto the page.
  • propels droplets of ink directly onto the medium
  • uses cyan, magenta, yellow and black
Laser Printer
  • produces high quality text and graphics
  • uses a non-impact
  • utilizes a laser beam to produce an image on a drum
  • light of the laser alters the electrical charge on the drum wherever it hits
  • the drum is then rolled through a reservoir of toner, which is picked up by the charged portions of the drum
  • the toner is transferred to the paper through a combination of heat and pressure
Magnetic-Ink Character Recognition


  • also known as MIRC
  • character recognition system that uses special ink and characters
  • used by banks to read unusual numbers and characters found on the bottom of checks
  • provides a secure, high-speed method of scanning and processing information



Optical-Character Recognition


  • also known as OCR
  • recognition of printed or written text characters by a light source and convert into ASCII code
  • analyzes the light and dark areas of the bitmap in order to identify each alphabetic letter and numeric digit
  • used to read retail price tag in departmental stores, in libraries to digitize and preserve their holdings and ect


Optical-Mark Recognition


  • also known as OMR
  • scans and senses the presence or absence of mark or character 
  • the use of "bubble sheets" for multiple-choice tests used by schools

High Definition Multimedia Interface port

High-Definition Multimedia Interface is also known as HDMI.

HDMI is :
  • compact audio/video interface for transmitting uncompressed digital data
  • connects digital audio/video sources for examples HD DVD player, PlayStation 3 to compatible digital audio devices like video projector and digital TV

Ethernet port

Ethernet port is a family of frame-based computer-networking technologies which connects the computer to the internet modem for local are networks (LAN).

Firewire port

Firewire port also known as High Performance Serial Bus (HPSB).

Firewire is :
  • allows connetion between a computer to many different types of peripheral devices
  • a very high-speed rate of data transfer that will accommodate multimedia applications for example digital camcorder

Parallel port

Parallel port is also known as :

  • printer port 
  • Centronics port



A Parallel port is :

  • socket on a computer used to connect various peripherals
  • to send or receive a huge amount of data in a short distance
  • allows eight data bits transferring simultaneously

Serial port

Serial port is :

  • A socket on a computer used to connect a modem, or other device especially in data acquisition terminal
  • runs at a very slow speeds
  • on the back of a PC is a male 9-pin connector
  • good for long distance

Universal Serial Bus port

Universal Serial Bus port also known as USB.

The USB is :

  • the most common type of computer port used in today's computers
  • used to connect devices like keyboards, mice, game controllers, printers, scanners, digital cameras ect
  • faster than older ports, such as serial and parallel ports

Plug and Play

Plug and Play is:

  • allows to add new components or devices to a system automatically 
  • for examples: headphone, microphone, mouse ect
  • recognizes the attached peripheral devices then adjust the appropriate internal settings when starting the computer

Network Interface Card

Network Interface Card also known as NIC.

Netwok Interface Card is :
  • a computer circuit board
  • a card that is installed in a computer to make connection between it and the network cable
  • provide a dedicated, full-time connection to a network

Sound Card

Also called :
  • Sound Board
  • Audio Adaptor

Sound Card is :
  • a plug-in card that records and plays back sound
  • provide an input port for a microphone or other sound source
  • output ports to speakers and amplifiers

Graphic Card

Also known as :

  • Video Card
  • Video Adapter
  • Graphic Adapter



Graphic Card is :

  • the plug-in card in a desktop computer
  • creates the electronic signals required by the monitor
  • an expansion card that allows the computer to send graphical information to a video display device

Flash Memory

Flash Memory is :


  • a non-volatile computer storage chip that can be electrically erased and reprogrammed.
  • primarily used in memory cards, USB flash drives, MP3 players and solid-state drives.
  • used for general storage and transfer of data between computers and other digital products.

ROM

ROM stands for Read-Only Memory.


ROM is :

  • nonvolatile
  • computer memory on which data has been prerecorded
  • data cannot be removed and can only be read
  • retain its contents even when the computer is turned off
  • used extensively in calculators and peripheral devices such as laser printer

Cache

Cache is :

  • to store data locally in order to speed up subsequent retrievals
  • Reserved areas of memory in every computer that are used to speed up instruction execution, data retrieval and data updating.
  • serve as staging areas, and their contents are constantly changing.
  • take advantage that same data item is often reused many times.
  • holds copies of recently accessed data such as a web page and pictures on web pages

RAM

RAM stands for Random Access Memory.


RAM is :

  • small, both in physical size and in the amount of data it can hold.
  • any storage location can be accessed directly
  • faster to read from and write to than the other kinds of storage in a computer, the hard disk, floppy disk, and CD-ROM.
  • data in RAM stays there only as long as your computer is running

System Unit

  • RAM
  • Cache
  • ROM
  • Flash Memory
  • Graphic Card
  • Sound Card
  • Network Interface Card
  • Plug and Play
  • Universal Serial Bus port (USB)
  • Serial port
  • Parallel port
  • Firewire port
  • Ethernet port
  • High Definition Multimedia Interface port (HDMI)

Vector Image

Vector Image is:
  • a computer image that uses a Wire Frame or Outlines to define a shapes area
  • made up of mathematical descriptions of paths and fills to define the graphic
  • is drawn in shapes, points, curves, polygon/s and lines called paths
  • tend to have a small electronic file size (KB or MB)
  • can be enlarged and there is no loss of image quality
  • not good at handling images that have textures such as Photos
  • can change the color of individual objects without worrying about individual pixels
  • not appropriate for use in producing realistic-looking photos and images

Multimedia


Multimedia is:
  • the use of computers or electronic device to present text, graphics, video, animation and sound in an integrated way
  • combinations made possible through the advancement of technology
  • can be accessed through computers or electronic devices and integrates the various forms together
  • usually recorded and played, displayed or accessed by information content processing devices, such as computerized and electronic devices
  • media and content that uses a combination of different content forms

Image Editor


Image Editor is:
  • software that allows images to be edited and also converted to different graphics formats
  • provides a variety of special features for altering images
  • specialized for modifying bit-mapped images such as GIFs, JPEGs and BMPs (eg. scanned photographs)
  • enable you to create and superimpose layers
  • cropping and resizing the image and using "filters" to adjust brightness, contrast and colors

HTML Editor

HTML Editor is:
  • stands for HyperText Markup Language which is used to develop web pages
  • an authoring tool and a software program that insert HTML code as user create HTML file
  • code editors offer add different colors to different HTML tags that can help in identification
  • WYSIWYG HTML editors provide an editing interface which resembles how the page will be displayed in a web browser

Desktop Publishing Program


Desktop Publishing Program is:
  • also known as DTP
  • a computer tool for both graphic and non-graphic materials combine together to produce documents like newsletters, books and brochures
  • allows user to use different typefaces, specify various margins and justifications, and embed illustrations and graphs directly into the text
  • enable user to create own illustration or insert illustrations created by other program
  • enable user to see on the display screen exactly how the document will appear when printed using the feature called WYSIWYG(What You See Is What You Get)

Bitmap Image

Bitmap Image is:
  • a type of graphic composed of pixels (picture element) in a grid
  • each pixel or "bit" contains color information for the image
  • has a fixed resolution which means that resizing a bitmap graphic can result in distortion and jagged edges
  • does not need to contain a bit of color-coded information for each pixel on every row
  • Some common bitmap formats are GIF, JPG or JPEG,TIFF, PNG, PICT, PCX and BMP

Audio Editing Software

Audio Editing Software is:
  • to create and record unique voice and music mix files
  • to edit recordings including cut and paste options and the ability to edit tag or media information
  • to record favorite podcasts, internet radio stations and other types of streaming audio. 
  • pull audio from a video or audio file, CDs, DVDs or sound card
  • to convert file formats (eg. from a MIDI to an MP3, WMA, WAV or OGG file)
  • can restore the sound of aged LPs or damaged audio recordings
  • to filter out background noises, static or other unwanted noise

Web Authoring

Web Authoring is:


  • a category of software that enables the user to develop a web site in a desktop publishing format
  • required HTML coding for the layout of the Web pages that the user designs
  • can be toggle back and forth between the graphical design and the HTML code
  • make changes to the Web page in either the design of the accompanying code
  • allows Web pages to be visually created like a desktop publishing program

Utility Suites

Utility Suites is:


  • a collection of different tools all packaged into one easy to use tool that optimize you computer
  • to help analyze, configure, optimize and maintain the computer
  • more appealing when Windows included fewer safety and maintenance features
  • examples, history cleaner, temp file cleaner, registry cleaner, Internet usage tracks cleaner, anit-virus

DBMS

DBMS is:


  • stands for DataBase Management System
  • a standard method of cataloging, retrieving, and running queries on data
  • controls the organization, storage, retrieval, security and integrity of data in a database
  • accept requests from the application
  • instructs the operating system to transfer the appropriate data
  • allows information system be change more easily as the user's requirements change such as store, modify and extract information from a database
  • examples of DBMS are MySQL, Oracle, and Microsoft Access

Spreadsheet

Spreadsheet is:
  • a computer application that acts as a paper or accounting worksheet
  • allows users to create and manipulate data and values
  • display multiple cells in two-dimentional and three-dimentional matrix or grid consisting of rows and columns
  • enable users to produce charts and graphs from the data
  • commonly used for financial information
  • ables to re-calculate the entire sheet automatically
  • examples of spreadsheet applications are Lotus 1-2-3 and Microsoft Excel