The difference between velocity and speed

I had never thought about this question before; I discussed it with some friends. Below is our summary for your reference. > Generally speaking, velocity and speed mean more or less the same thing – there isn’t much difference between them. > Velocity has a more technical connotation. > There’s a way to better understand the difference between them: velocity is speed with direction – in other words, velocity is speed that includes direction. The term speed, on the other hand, doesn’t imply any direction. An example will make this clearer: for instance, the “speed of a chemical reaction” refers to the rate at which that reaction occurs, while “the speed at which they built the factory” refers to the rate of construction. > Therefore, it’s generally safer to use velocity rather than speed, as velocity has a wider range of applications. Feel free to join the discussion! :)

:)Perhaps we can use the \"rate\" in physical definitions to explain \"speed\", and use \"speed\" to explain \"velocity\"; this seems to allow for an intuitive understanding that velocity is a physical quantity that builds on speed by adding a vector component: P

I really don’t feel any meaningful difference. It is in technical terms that \"velocity\" is commonly used. Does anyone know the fundamental difference between the two?