USB hardware
Videos
The initial versions of the USB standard specified connectors that were easy to use and that would have high life spans; revisions of the standard added smaller connectors useful for compact portable
Various legacy USB connectors along a centimeter ruler for scale. From left to right: Micro-B plug Proprietary UC-E6 connector used on many older Japanese cameras for both USB and analog AV output Mini-B plug (inverted) Standard-A receptacle (inverted; non-compliant because official USB specifications do not allow for extension cables) Standard-A plug Standard-B plug
Prohibited USB extension cable, plug on the left, receptacle on the right. (USB does not allow extension cables. Non-standard cables may work but cannot be presumed reliable.)
A yellow charge-only "USB" Type-A receptacle and a USB 3.0 Type-A receptacle, both upside-down, on a front panel with card reader
A blue Standard-A USB receptacle without USB 3.0 contacts fitted
Common external power supply
Videos
The common external power supply was a European Commission specification for a universal charger for smartphones sold within the European Union. The specification included the use of a USB Micro-B con
Common external power supply and the USB Standard-A and Micro-B ends of the detachable cable
Examples of different charger connectors previously used by manufacturers (Samsung, Motorola, Nokia, Sony Ericsson)