USB types

USB connectors come in several types: the default sizes (USB A, USB B and USB C), Mini USB type A and B and Micro USB A and B.

USB A has an elongated, rectangular form and can carry power and data. The USB A plug is used to provide a downstream connection to controllers or hubs.

USB B is narrower, squarer shaped and commonly used for connecting peripheral devices such as printers and scanners, or as an upstream port for USB hubs. USB B connectors are still in use today but slowly being phased out and replaced with USB C connectors and ports.

USB C is the newest USB interface, launched in 2014. With a narrower, more elongated shape than USB A, USB C has more pins enabling it to transfer a larger amount of power and data. USB typc C cable is currently compatible with Apple MacBooks with Thunderbolt 3 ports, Chromebooks and the most recent laptop models.

USB Mini plugs were designed for use on USB peripheral devices such as older smartphone models or digital cameras While still in use on some devices, USB Mini is now broadly seen as a legacy connector, and not certified as compatible with newer devices.

USB Micro is an even slimmer version of the USB mini-plugs, being better suited to newer models of OTG (on-the-go) devices while enabling the same level of connectivity. USB Micro is now the standard connection type for charging smartphones.

USB versions

USB 1.0 is the original USB standard, where the limit for data transfer is 12Mbps. USB 1.0 was originally designed to connect peripheral devices such as mice, keyboards and game controllers. As the simplicity of the USB connector interface grew in popularity, the USB standard evolved to USB 2.0 in 2000.

USB 2.0 provided a much higher connection speed with a throughput of 480Mbps. The cable is also known as High Speed. The standard length of USB 2.0 passive cables is 5 meters. Active cables, on the other hand, can have a length of up to 20 meters. 

The USB 3.0 specification was released in 2008. This type is also known as SuperSpeed, being able to transfer data at a speed up to 5.0Gbps. SuperSpeed USB cables can be told apart with the SS logo and the blue color in the internal part of plugs and port. The standard length for passive cables is 3 meters, while active cables can be up to 20 meters long. The 2nd generation of USB 3.1 can transfer up to 10Gbps of data.

HDMI

HDMI, an acronym for High-Definition Multimedia Interface, is an interface for transmitting digital audio and video data from a source device to a presentation/output device such as a projector or display or digital audio device. The initial HDMI standard HDMI 1.0 was created in 2002 as a collaboration between major technology manufacturers including Panasonic, Phillips, Sony and Toshiba. Since then, this data transmission interface has evolved and improved, and several versions of HDMI are now available. Each new HDMI version has brought about an exponential increase in audio/video capacity, resolution, improved color spaces, and advanced features such as CEC (Consumer Electronics Control), 3D and Ethernet data connection.