USB (Universal Serial Bus) is a widely used standard for connecting devices to computers and other electronic devices. It was developed to simplify and standardize the connection of peripherals like keyboards, mice, printers, external storage devices, and more. Here’s an overview of USB: Key Features of USB:1. Plug-and-Play: Devices can be connected and used without restarting the computer.2. Hot-Swappable: Devices can be connected or disconnected while the computer is running.3. Power Delivery: USB can provide power to connected devices, eliminating the need for separate power adapters in many cases.4. Versatility: Supports a wide range of devices, from storage to audio/video peripherals.5. Scalability: Multiple devices can be connected using USB hubs. USB Versions:- USB 1.x (1996): - Speed: 1.5 Mbps (Low Speed) or 12 Mbps (Full Speed). - Largely obsolete but was the first standard.- USB 2.0 (2000): - Speed: Up to 480 Mbps. - Still widely used for many devices.- USB 3.x (2008 onwards): - USB 3.0: Up to 5 Gbps. - USB 3.1: Up to 10 Gbps. - USB 3.2: Up to 20 Gbps. - Backward compatible with USB 2.0.- USB4 (2019): - Speed: Up to 40 Gbps. - Based on Thunderbolt 3 technology. - Supports multiple data and display protocols. USB Connector Types:1. USB-A: The standard rectangular connector found on most computers and chargers.2. USB-B: Often used for printers and other larger devices.3. Mini-USB: Smaller connector used in older devices (mostly obsolete).4. Micro-USB: Common in older smartphones and small devices.5. USB-C: Reversible, compact, and capable of high-speed data transfer and power delivery. Used in modern devices like laptops, smartphones, and tablets. USB Power Delivery (USB-PD):- A protocol for delivering higher power levels (up to 100W) over USB-C. - Enables fast charging for devices like laptops and smartphones. Applications:- Data Transfer: External drives, flash drives, and smartphones. - Peripherals: Keyboards, mice, printers, and scanners. - Audio/Video: Webcams, microphones, and external displays. - Charging: Smartphones, tablets, and other devices.USB continues to evolve, with USB-C and USB4 becoming the standard for modern devices due to their speed, versatility, and power delivery capabilities.