# USB connector > the connectors (plugs and receptacles) for USB communications protocols and power **Wikidata**: [Q41796309](https://www.wikidata.org/wiki/Q41796309) **Wikipedia**: [English](https://en.wikipedia.org/wiki/USB_hardware) **Source**: https://4ort.xyz/entity/usb-connector ## Summary A USB connector is an electrical connector system designed to facilitate USB communications protocols and power transmission between devices. These connectors exist as physical interfaces—specifically plugs and receptacles—that serve as subclasses of electrical signal and DC power connectors. They encompass a range of types, most notably the modern USB-C and various legacy USB connectors. ## Key Facts - **Official Name:** USB connector. - **Component Types:** The system consists of "USB plugs" (which connect to receptacles) and "USB receptacles" (which accept plugs). - **Modern Standard (USB-C):** A 24-pin reversible-plug serial digital connector designed to replace all other USB connectors. It is capable of carrying all USB data protocols and power levels up to 240 W. - **Legacy Class:** Defined as the class of all USB connectors other than Type-C, which USB-C is intended to replace. - **Functionality:** Serves as both an electrical signal connector and a DC power connector. - **Sub-Classifications:** Includes specific classes such as "USB 2 connector" (carrying only USB 1–2 and power) and "Full-Featured Type-C" (with exhaustive capabilities). - **Composition:** Physically composed of electrical contacts and structural elements. - **Aliases:** Also referred to as "prise USB" or "port USB." ## FAQs ### Q: What is the primary difference between USB-C and legacy USB connectors? A: USB-C is a 24-pin reversible system designed to replace all legacy connectors, featuring the capacity to carry all USB data protocols and higher power levels (up to 240 W). Legacy connectors encompass all pre-Type-C USB types that are now being phased out by the USB-C standard. ### Q: What components make up a USB connector? A: A USB connector is physically composed of electrical contacts and structural elements. Functionally, the class is divided into "USB plugs," which insert into ports, and "USB receptacles," which accept the plugs. ### Q: Can a USB connector transmit both data and power? A: Yes, USB connectors function as both electrical signal connectors and DC power connectors. Specific types, like the USB 2 connector class, carry USB 1–2 data protocols alongside power, while USB-C offers more exhaustive capabilities. ## Why It Matters USB connectors are the fundamental infrastructure for modern device connectivity, serving as the standard interface for both data communication and power delivery. They matter because they provide a unified method for connecting external computer peripherals, ranging from keyboards to high-speed storage drives. The shift from legacy connectors to USB-C represents a significant consolidation in hardware design. By creating a single connector system that supports exhaustive data protocols and high-wattage power (up to 240 W), the standard reduces the need for multiple proprietary cables and ports. This evolution simplifies user experiences and enables new technologies, such as charging laptops via USB rather than dedicated power bricks. As a subclass of both signal and power connectors, the USB connector plays a critical role in the interoperability of consumer electronics. ## Notable For - **Unification of Standards:** The USB-C class is explicitly designed to replace all other legacy USB connectors, creating a single standard for data and power. - **High Power Delivery:** Unlike many early signal connectors, the USB-C system supports power delivery in either direction up to 240 W. - **Reversible Design:** The USB-C connector is a 24-pin reversible-plug serial digital connector, improving usability compared to older directional plugs. - **Dual Role:** It uniquely operates as a combined electrical signal connector, interface standard, and DC power connector. ## Body ### Classification and Hierarchy The USB connector is an electrical connector system that functions as a subclass of "electrical signal connector," "DC power connector," and "external computer connector." It is the physical manifestation of the USB standard (part of the USB parent class), comprising distinct components known as "USB plugs" and "USB receptacles." The ecosystem is broadly categorized into two primary classes: 1. **USB-C:** The modern standard defined as a 24-pin reversible-plug serial digital connector. 2. **Legacy USB Connector:** The class encompassing all USB connectors other than Type-C. ### Technical Specifications The USB connector system supports a wide range of capabilities depending on the specific class. * **USB-C:** This connector type is designed to carry all USB data protocols and power levels. It features a reversible plug design and supports power flow in either direction, up to 240 W. * **USB 2 Connector:** A specific class of connectors (both Type-C and legacy) that carries only USB 1–2 protocols and power. This contrasts with Full-Featured Type-C and legacy USB 3 connectors, which support a wider subset of capabilities. ### Physical Composition Structurally, every USB connector consists of: * **Electrical contacts:** For transmitting signals and power. * **Structural elements:** To ensure physical stability and correct insertion. Variants include Standard-A, Standard-B, Micro-A, Micro-B, Mini-A, Mini-B, and Powered-B receptacles and plugs, all of which fall under the "Legacy" umbrella being succeeded by the USB-C standard. ## References 1. [Source](https://www.usb.org/document-library/usb-31-legacy-cable-and-connector-revision-10) 2. [Source](https://www.usb.org/document-library/universal-serial-bus-31-legacy-connectors-and-cable-assemblies-compliance-document) 3. [Source](https://www.usb.org/document-library/usb-32-revision-11-june-2022) 4. [Source](https://www.usb.org/document-library/usb-type-cr-connectors-and-cable-assemblies-compliance-document-rev-21b) 5. [Source](https://www.usb.org/document-library/usb-type-cr-cable-and-connector-specification-release-24)