USB stands for Universal Serial Bus ("Porta Universal", in Portuguese), a type of technology that allows the connection of peripherals without the need to turn off the computer, in addition to transmitting and storing data.
Peripherals are devices or cards that send and receive information from the computer, in connection with the machine's CPU.
Examples of the most common peripherals are: pendrives, printers, scanners, CD and DVD readers or recorders, card readers, mice, keyboards, webcam and etc.
Currently, most of these peripherals are connected to the computer via UBS connection.
Current USB connections are PnP standard (Plug and Play or “Plugar e Uso”, in Portuguese), which helped to reduce all the complications in the configuration of these devices, in order to make life easier for the user.
The USB standard was developed by a consortium of companies in 1995, including: Microsoft, Apple, Hewlett-Packard, NEC, Intel and Agere. However, the first “USB ports” only started to be used in computers manufactured after 1997.
It was very difficult for these companies to find a consensus, so opinions were divided and two distinct groups were formed: UHCI (Universal Host Controller Interface) supported by Intel, and which transfers part of the protocol processing to the software.
OHCI (Open Host Controller Interface) supported by Compaq, Microsoft and National Semiconductor, which shifted most of the effort to the electronic controller.
The universal symbol of the USB system is a trident of Neptune (in Roman mythology it was known to be the god of underground and underwater waters). Theoretically, the different shapes of the trident's tips – circle, triangle and square – would represent the varieties of devices that could be supported by USB technology.
USB 3.0
The first version of USB was called USB 0.7, released in November 1994. This model could achieve a maximum data transfer speed of 1.5 MB per second.
In 2009, USB 3.0, also known as superspeed, which has the capacity to transfer up to 625 MB per second.
Currently, all electronic devices are produced to be able to adapt to USB technology.