Intro To Information Technology

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

• 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

• 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

• 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

• Disk Caching
• Gile Compression
• File Decompression
• Internet Hard Drive
• Optical Disc Drive
• Solid-State Storage

• 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

• 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

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

• 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

• 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

• 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

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

• 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

• 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

• 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

• 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

• 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

• 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