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USB Info: Frequently Asked Questions

Basic Information

Q1: What are the different types of USB plugs and ports?
A1: The different types of USB ports are highlighted below.

Hi-Speed USB (USB 2.0)

USB 2.0 Standard-A plug and receptacle. A Standard-A USB plug inserts into a USB host or a hub and carries both power and data.

USB 2.0 Standard-B plug and receptacle. A Standard-B plug typically plugs into a large device, such as a printer.

Micro-USB 2.0 (Micro-A, Micro-B and Micro-AB) plug and receptacle. Micro-USB connectors carry both power and data, and support USB On-The-Go. They are used in small portable devices, such as smartphones, digital cameras, GPS devices and more.

SuperSpeed USB (USB 3.0)

SuperSpeed USB cables and connectors contain 5 additional wires compared to USB 2.0. If you have a SuperSpeed USB plug and a Hi-Speed USB receptacle, the device will work, at Hi-Speed USB rates. If you have a Hi-Speed USB receptacle and a SuperSpeed USB plug, the device will work, at Hi-Speed USB rates. In order to achieve the data throughput of SuperSpeed USB, a user must have a SuperSpeed USB host, a SuperSpeed USB device and a SuperSpeed USB cable.

USB 3.0 Standard-A plug and receptacle. A Standard-A USB plug inserts into a USB host, or a hub, and carries both power and data. The USB 3.0 Standard-A plug and receptacle are backward compatible with the USB 2.0 Standard-A plug and receptacle.

USB 3.0 Standard-B plug and receptacle. A Standard-B plug typically plugs into a large device, such as a printer. The USB 3.0 Standard-B receptacle is backward compatible with the USB 2.0 Standard-B plug.

Micro-USB 3.0 (Micro-B) plug and receptacle. A Micro-USB 3.0 plug is for small, portable devices, such as smartphones, digital cameras, GPS devices and more. The Micro-USB 3.0 receptacle is backward compatible with the  Micro-USB 2.0 plug.

Q2: Will I need special software to run USB?
A2: For USB 2.0, there is no special software needed. Current operating systems all support USB 2.0.

Currently, for USB 3.0, host software is required, delivered by the host vendor. In August 2011, Microsoft announced that it will support USB 3.0 in its Windows 8 operating system, which will become the de facto software stack. Additionally, USB 3.0 is currently supported in the Linux kernel.
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Q3: What kinds of USB peripherals can I connect to my PC?
A3: Virtually all USB peripherals can be connected to a PC, i.e. mobile phones, digital cameras and camcorders, HDDs, SSDs, set-top boxes, TVs, gaming consoles, GPS devices, digital scanners, printers, keyboards, mice and digital joysticks.

Q4: How many USB peripherals can I connect at once?
A4: Technically, you can connect up to 127 individual USB peripherals at one time. Due to the fact that some devices reserve USB bandwidth, the practical maximum of devices is less than the theoretical maximum. However, PCI-USB add-in cards provide an independent USB bus to which even more peripherals can be connected.
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Q5: Where can I find out what USB products are currently available...or on the way?
A5: You've come to the right place! This website highlights Current USB Products featured on the USB integrators list. All of these products listed on our site have undergone USB-IF Compliance and Certification testing and passed a specific set of tests to help assure that they will function correctly on your computer.

Q6: Where can I learn more technical details about USB?
A6: The technical specifications and presentations are available from the USB Implementers Forum on the USB Developers Site.

Q7: What does it mean when a product is USB compliant and why should I care?
A7: Compliance/certification means the USB product has been tested by the USB-IF to meet the specification and for interoperability, and this is important not only to OEMs but to consumers, because products tested and certified by the USB-IF will work together.

Compliance testing exists to help manufacturers measure how well their products match the respective USB specification. Please visit the USB Compliance Program page for more details.

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