The “best speed” depends on its purpose; for internet speed, anything over 100 Mbps is considered fast for general use, while activities like 4K streaming and gaming on multiple devices benefit from speeds of 200 Mbps or more, and 1 Gbps is ideal for households with many devices and heavy usage. For human travel, the fastest speed achieved was over 39,000 km/h (24,000 mph) by astronauts on the Apollo 10 mission.