 The ubiquitous USB Type A. Released in 1995, Type A is for host computer connections. You likely still have a compatible port on your desktop machine today. In 96, the chunky Type B connector came along for connecting to peripherals, known to many simply as printer cable. It also connected to Arduino. Type B is a bit large for a cell phone, so in 2000, mini-B was introduced, followed seven years later by the flatter, more reliable, micro-B connector. With the release of USB 3 came extra chunky Type B connectors, with backward compatible sockets, odd but cool. Eventually, we take a big step forward with USB C. It's faster, reversible, and uses the same connector for host and peripheral. It's the one connector to rule them all, until the next one comes out.