Electronic commerce, commonly known as e-commerce, ecommerce or e-comm, refers to the buying and selling of products or services over electronic systems such as the Internet and other computer networks. However, the term may refer to more than just buying and selling products online. It also includes the entire online process of developing, marketing, selling, delivering, servicing and paying for products and services. The amount of trade conducted electronically has grown extraordinarily with widespread Internet usage. The use of commerce is conducted in this way, spurring and drawing on innovations in electronic funds transfer,supply chain management, Internet marketing, online transaction processing, electronic data interchange (EDI), inventory management systems, and automated data collection systems. Modern electronic commerce typically uses the World Wide Web at least at one point in the transaction's life-cycle, although it may encompass a wider range of technologies such as e-mail, mobile devices and telephones as well.
A large percentage of electronic commerce is conducted entirely in electronic form for virtual items such as access to premium content on a website, but mostly electronic commerce involves the transportation of physical items in some way. Online retailers are sometimes known as e-tailers and online retail is sometimes known as e-tail. Almost all big retailers are now electronically present on the World Wide Web.
Electronic commerce that takes place between businesses is referred to as business-to-business or B2B. B2B can be open to all interested parties (e.g. commodity exchange) or limited to specific, pre-qualified participants (private electronic market). Electronic commerce that takes place between businesses and consumers, on the other hand, is referred to as business-to-consumer or B2C. This is the type of electronic commerce conducted by companies such as Amazon.com. Online shopping is a form of electronic commerce where the buyer is directly online to the seller's computer usually via the internet. There is often no intermediary service involved, and the sale or purchase transaction is completed electronically and interactively in real-time. However in some cases, an intermediary may be present in a sale or purchase transaction, or handling recurring or one-time purchase transactions for online games.
Electronic commerce is generally considered to be the sales aspect of e-business. It also consists of the exchange of data to facilitate the financing and payment aspects of business transactions.
Electronic commerce, commonly known as e-commerce, ecommerce or e-comm, refers to the buying and selling of products or services over electronic systems such as the Internet and other computer networks. However, the term may refer to more than just buying and selling products online. It also includes the entire online process of developing, marketing, selling, delivering, servicing and paying for products and services. The amount of trade conducted electronically has grown extraordinarily with widespread Internet usage. The use of commerce is conducted in this way, spurring and drawing on innovations in electronic funds transfer,supply chain management, Internet marketing, online transaction processing, electronic data interchange (EDI), inventory management systems, and automated data collection systems. Modern electronic commerce typically uses the World Wide Web at least at one point in the transaction's life-cycle, although it may encompass a wider range of technologies such as e-mail, mobile devices and telephones as well.
A large percentage of electronic commerce is conducted entirely in electronic form for virtual items such as access to premium content on a website, but mostly electronic commerce involves the transportation of physical items in some way. Online retailers are sometimes known as e-tailers and online retail is sometimes known as e-tail. Almost all big retailers are now electronically present on the World Wide Web.
Electronic commerce that takes place between businesses is referred to as business-to-business or B2B. B2B can be open to all interested parties (e.g. commodity exchange) or limited to specific, pre-qualified participants (private electronic market). Electronic commerce that takes place between businesses and consumers, on the other hand, is referred to as business-to-consumer or B2C. This is the type of electronic commerce conducted by companies such as Amazon.com. Online shopping is a form of electronic commerce where the buyer is directly online to the seller's computer usually via the internet. There is often no intermediary service involved, and the sale or purchase transaction is completed electronically and interactively in real-time. However in some cases, an intermediary may be present in a sale or purchase transaction, or handling recurring or one-time purchase transactions for online games.
Electronic commerce is generally considered to be the sales aspect of e-business. It also consists of the exchange of data to facilitate the financing and payment aspects of business transactions.
- Input and output devices are typically housed externally to the main computer chassis. The following are either standard or very common to many computer systems.
Wheel mouse
Input
Main article: Input deviceText input devices
Keyboard - a device to input text and characters by depressing buttons (referred to as keys or buttons).
Pointing devicesMouse - a pointing device that detects two dimensional motion relative to its supporting surface.
Optical Mouse - uses light (laser technology) to determine mouse motion.
Trackball - a pointing device consisting of an exposed protruding ball housed in a socket that detects rotation about two axes.
Touchscreen - senses the user pressing directly on the monitor.
Gaming devices
Joystick - a hand-operated pivoted stick whose position is transmitted to the computer.
Game pad - a hand held game controller that relies on the digits (especially thumbs) to provide input.
Game controller - a specific type of controller specialized for certain gaming purposes.
Image, Video input devices
Image scanner - a device that provides input by analyzing images, printed text, handwriting, or an object.
Web cam - a video camera used to provide visual input that can be easily transferred over the internet.
Audio input devices
Microphone - an acoustic sensor that provides input by converting sound into electrical signals.
[edit]Output
Main article: Output devicePrinter - a device that produces a permanent human-readable text of graphic document.
Dot Matrix PrinterLaser PrinterCiode display
OLED - Organic Light-Emitting Diode
Monitors
- CD (compact disc) - the most common type of removable media, suitable for music and data।
- CD-ROM Drive - a device used for reading data from a कद
- CD Writer - a device used for both reading and writing data to and from a CD.
DVD (digital versatile disc) - a popular type of removable media that is the same dimensions as a CD but stores up to 12 times as much information। It is the most common way of transferring digital video, and is popular for data storage।
- DVD-ROM Drive - a device used for reading data from a DVD.
DVD Writer - a device used for both reading and writing data to and from a DVD.
DVD-RAM Drive - a device used for rapid writing and reading of data from a special type of DVD.
Blu-ray Disc - a high-density optical disc format for data and high-definition video. Can store 70 times as much information as a CD.
BD-ROM Drive - a device used for reading data from a Blu-ray disc.
BD Writer - a device used for both reading and writing data to and from a Blu-ray disc.
HD DVD - a discontinued competitor to the Blu-ray format.
Floppy disk - an outdated storage device consisting of a thin disk of a flexible magnetic storage medium. Floppies are used today mainly for loading device drivers not included with an operating system release (for example, RAID drivers).
Iomega Zip drive - an outdated medium-capacity removable disk storage system, first introduced by Iomega in 1994.
USB flash drive - a flash memory data storage device integrated with a USB interface, typically small, lightweight, removable, and rewritable. Capacities vary, from hundreds of megabytes (in the same range as CDs) to tens of gigabytes (surpassing, at great expense, Blu-ray discs).
Tape drive - a device that reads and writes data on a magnetic tape, used for long term storage and backups.
- CD (compact disc) - the most common type of removable media, suitable for music and data।
- CD-ROM Drive - a device used for reading data from a कद
- CD Writer - a device used for both reading and writing data to and from a CD.
DVD (digital versatile disc) - a popular type of removable media that is the same dimensions as a CD but stores up to 12 times as much information। It is the most common way of transferring digital video, and is popular for data storage।
- DVD-ROM Drive - a device used for reading data from a DVD.
DVD Writer - a device used for both reading and writing data to and from a DVD.
DVD-RAM Drive - a device used for rapid writing and reading of data from a special type of DVD.
Blu-ray Disc - a high-density optical disc format for data and high-definition video. Can store 70 times as much information as a CD.
BD-ROM Drive - a device used for reading data from a Blu-ray disc.
BD Writer - a device used for both reading and writing data to and from a Blu-ray disc.
HD DVD - a discontinued competitor to the Blu-ray format.
Floppy disk - an outdated storage device consisting of a thin disk of a flexible magnetic storage medium. Floppies are used today mainly for loading device drivers not included with an operating system release (for example, RAID drivers).
Iomega Zip drive - an outdated medium-capacity removable disk storage system, first introduced by Iomega in 1994.
USB flash drive - a flash memory data storage device integrated with a USB interface, typically small, lightweight, removable, and rewritable. Capacities vary, from hundreds of megabytes (in the same range as CDs) to tens of gigabytes (surpassing, at great expense, Blu-ray discs).
Tape drive - a device that reads and writes data on a magnetic tape, used for long term storage and backups.
- The motherboard is the main component inside the case. It is a large rectangular board with integrated circuitry that connects the other parts of the computer including the CPU, the RAM, the disk drives (CD, DVD, hard disk, or any others) as well as any peripherals connected via the ports or the expansion slots.
Components directly attached to the motherboard include:
- The central processing unit (CPU) performs most of the calculations which enable a computer to function, and is sometimes referred to as the "brain" of the computer. It is usually cooled by a heat sink and fan. Newer CPUs include an on-die Graphics Processing Unit (GPU).
The chip set mediates communication between the CPU and the other components of the system, including main memory.
RAM (random-access memory) stores resident part of the current running OS (OS core and so on) and all running processes (application parts, using CPU or input/output (I/O) channels or waiting for CPU or I/O channels).
The BIOS includes boot firmware and power management. The Basic Input Output System tasks are handled by operating system drivers. Newer motherboards use Unified Extensible Firmware Interface instead of BIOS.
Internal buses connect the CPU to various internal components and to expansion cards for graphics and sound.
Current
The north bridge memory controller, for RAM and PCI Express
PCI Express, for expansion cards such as graphics, lannd and physics processors, and high-end network interfaces
PCI, for other expansion cards
SATA, for disk drives
ATA
Obsolete
AGP (superseded by PCI Express)
VLB VESA Local Bus (superseded by AGP)
ISA (expansion card slot format obsolete in PCs, but still used in industrial computers)
External bus controllers support ports for external peripherals. These ports may be controlled directly by the south bridge I/O controller or based on expansion cards attached to the motherboard through the PCI bus.
USB
FireWire
eSATA
SCSI
