PCIe 4.0, or Peripheral Component Interconnect Express 4.0, is a high-speed interface standard used to connect various hardware components in computers, such as graphics cards and storage devices. It offers double the data transfer rate of its predecessor, PCIe 3.0, reaching speeds of up to 64 gigabits per second (Gbps) per lane. This improvement allows for faster communication between components, enhancing overall system performance. The PCIe 4.0 standard is particularly beneficial for applications requiring high bandwidth, such as gaming, data centers, and artificial intelligence. It supports more devices and provides better efficiency, making it a popular choice for modern motherboards and graphics cards.