Changing Temperature, Changing Density. Most matter increases in volume when it gets hotter. For example, if an iron rod is heated, it will get longer and fatter and its density will decrease. This happens because the mass of the rod stays the same, but its volume increases. The increase in the volume of matter with increasing temperature is called expansion. When cooled down, most matter decreases in volume and increases in density. This decrease in volume is called contraction.
USB-C also builds on the new USB 3.1 standard so to all intents and purposes is the connection type that brings in the new power and speed advantages of USB 3.1. USB-C is still backwards compatible with existing USB variants, but that of course requires adapters.
USB 1.1 could transfer data at 12 Mbit/s. That is 1.4 Megabytes per second. Back in the day when a floppy disk could hold 1.4 Megabytes, that was fast. USB 2.0 was released in 2000, sporting a theoretical throughput of 480 Mbit/s. However, practically it works at 280 Mbit/s, which is around 35 Megabytes per second.