Later USB designs bring that current up to 0. Depending on the age of your device, you may have one or several versions of USB ports on your devices. Most people will be more familiar with the physical shape of USB connectors. These typically feature a flat rectangular plug the male connector at one end that fits into the port on your computer or power module the receptacle.
The other end of a charging wire will either feature the same type of plug, or one of several shapes that have developed over the years for connecting to different devices. This square-shaped plug is often used to connect computers with printers, scanners or similar devices.
USB 3. These plugs were used for charging older mobile phones, cameras and MP3s but are largely redundant now. USB 2. Click on the links below to jump to the relevant sections: What is a USB charging port? Unlike PCs today, machines from 30 years ago sported a glut of wildly different sockets and communication systems. Connecting peripherals and devices to such computers was often a frustrating experience, thanks to the oddities and limitations of each interface.
Source: Recycled Goods. Printers and scanners hooked up to a parallel port , via a pin connector, and everything else via the classic serial port. What if you accidentally stuck a mouse into the socket for the keyboard? It just wouldn't work, as the PC wouldn't know that the wrong device had been plugged in. In fact, none of these interfaces could identify what the device was: essentially, you'd have tell the computer what it was and manually install the right drivers for it.
If all went well, with a bit of luck and a quick reboot after the driver install, that was all you needed to get things working. A familiar sight to '90s PC users trying to attach a peripheral. Source: WinWorld. Naturally, consumers wanted something better: 'one port to rule them all,' so to speak.
A socket that you could plug devices in and out of, without having to restart the machine, and devices could be instantly recognized and configured for you. System vendors wanted something more universal as well, to replace the need for lots of different sockets, and be cheaper to produce. It would also need to have the scope to be developed and improved over the years, all while retaining backwards compatibility. Occasionally, in the world of computing, the planets align and set in motion a period of harmonious productivity, to the benefit of everyone.
In , such an event took place when Intel, Microsoft, IBM, Compaq, DEC, and Nortel formed a consortium, agreeing that the time was right to create a new connection system, that would meet everyone's desires and needs.
Within a space of just two years, a full specification was published, along with the chips to control it all. It boasted a clean, simple design and offered lots of performance. The uptake of the new system was slow at the beginning though, and it wasn't until version 1. It was this or the dance. No contest. Source: Microsoft. The changes in the revision were fairly minor, mostly concerning power management and device compatibility, but that wasn't what kickstarted USB adoption.
Instead, it was Microsoft adding USB 1. There was also Microsoft's heavy marketing of the phrase " Plug and Play " -- a design philosophy and system requirements for PCs that had the goal of removing the complexity of setting up computers and peripherals. While not the most robust of systems, USB was a perfect poster child for it. But the biggest advert for USB came about through Apple's decision to wholeheartedly jump on board, with the release of a product that would shake up the whole PC industry.
Goodbye to beige and the old ports - Apple's first iMac. Source: Wikipedia. Launched in August , the original iMac was bright and bold, and one of the first so-called ' legacy-free' PCs. This term was used to indicate that the machine eschewed all of the old ports and devices: everything in it would be the latest hardware. Although it wasn't a hit with the critics to begin with, it went on to sell in huge numbers -- its popularity put USB well and truly on the map, although it would be quite a few years before Windows-based computers were sold without any concessions to the ports of the past.
The USB specification went on to have several revisions, with the major ones being 2. But we'll come back to that later on. For now, let's take a look at how the Universal Serial Bus actually works and what makes it so much better that the systems it replaced.
Computer owners have the option to purchase cards that they can install in their computers to give USB 3. But hardware support is just part of the problem -- you also need support from your operating system. Recent distributions of the Linux operating system support USB 3. You might not think data transfer cables create controversy. That product is Light Peak , a data transfer technology that has an initial top data transfer speed of 10 gigabits per second with future theoretical speeds reaching gigabits per second.
Since Intel is a major manufacturer of chips, only a few computers with motherboards made by other companies currently support USB 3. Intel representatives deny such claims.
In the meantime, you can find computers and accessories that incorporate USB 3. Sign up for our Newsletter! Mobile Newsletter banner close. Mobile Newsletter chat close. Mobile Newsletter chat dots. Mobile Newsletter chat avatar.
Mobile Newsletter chat subscribe. Computer Hardware. Printers connected to parallel printer ports, and most computers only came with one. Things like external storage media, which need a high-speed connection into the computer, would use the parallel port as well, often with limited success and not much speed.
Modems used the serial port , but so did some printers and a variety of odd things like personal digital assistants PDAs and digital cameras.
Most computers had at most two serial ports, and they were very slow in most cases. Devices that needed faster connections came with their own cards, which had to fit in a card slot inside the computer's case. Unfortunately, the number of card slots is limited and some of the cards are difficult to install.
USB Cables and Connectors " ". USB Hubs " ". The USB Process When the host powers up, it queries all of the devices connected to the bus and assigns each one an address. The host also finds out from each device what type of data transfer it wishes to perform: Interrupt - A device like a mouse or a keyboard , which will be sending very little data, would choose the interrupt mode.
Bulk - A device like a printer, which receives data in one big packet, uses the bulk transfer mode. Was this page helpful? Thanks for letting us know! Email Address Sign up There was an error. Please try again. You're in! Thanks for signing up. There was an error. Tell us why! More from Lifewire. USB-C vs. Lightning: What's the Difference? USB 3: What's the Difference? Your Privacy Rights. To change or withdraw your consent choices for Lifewire.
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