vectors

magnitude + direction

e.g displacement，speed

scalars

magnitude

e.g distance，velocity

Vectors which magitude/size and directions.

Scalers which only have the magitude/size.

Distance is the scalar quantity which have the distance without direction.

When talk about the movement, the change in position, and give its direction called displacement.

Time only has one direction.

Speed is only a scaler quantity which it doesn't have direction.

Speed with direction is a vector quantity which it called velocity.

If you are thinking about change in position and the direction that it is displacement, without the direction is distance.

矢量：既有大小又有方向的量。

标量：只具有数值大小，而没有方向，部分有正负之分。

物体移动快慢的标量是速率。

距离是一个物体移动的远近程度。