The Universal Serial Bus (USB) replaces earlier interfaces (such as serial and parallel ports), and was designed to standardize the connection of computer peripherals (including keyboards, pointing devices, digital cameras, printers, portable media players, disk drives and network adapters) to personal computers. USB was designed to faciliate communication and supply electric power to external devices. It has now become commonplace on other devices, such as smartphones, PDAs and video game consoles.
Wi-Fi is a wireless communication scheme based on the Institute of Electrical and Electronics Engineers' (IEEE) 802.11 standard which allows electronic devices to exchange data and connect to the internet via a wireless local area network (WLAN) using radio waves with a range of up to 20m.
Bluetooth is a short-wavelength microwave wireless personal area network (PAN) technology standard for exchanging data over short distances (ISM band 2400 to 2480 MHz). Bluetooth was standardized as IEEE 802.15.1, but the standard is no longer maintained. Bluetooth provides a much shorter propagation range compared to Wi-fi and therefore in general it has a lower power consumption.
More info coming soon... Wireless USB, HDMI (High-Definition Multimedia Interface), VGA, DVI, Ethernet, GPIO, UART, I2C, I2S audio, SPI bus, Universal mouse, Universal keyboard, transistor power.