What is displacement and velocity?

What is displacement and velocity?

Displacement is a vector quantity that specifes an object's movement relative to some starting position. If you walk 3 meters east and then 4 meters west your total displacement is 1 meter west.

Velocity is a vector quantity that specifes the rate of change of an object's displacement. If \vec s(t) is the displacement vector as a function of time then the instantaneous velocity vector is:

\vec v(t) = \frac {d \vec s(t)} {dt}

The average velocity of an object over a period \Delta t is:

\vec v_{avg} = \frac {\Delta \vec s}{\Delta t} .

this is all about
initial velocity v_i
final velosity v_f
acceleration constant a
time t
relation between them is
v_f=at+v_i
there are two types of displacement
velocity constant that is simple: s=vt
the other one is acceleration constant: s=\int v_f dt=\int (v_i+at)dt=\int v_i dt+\int at dt=v_i t+a\frac {t^2}{2}
so
s=v_i t+\frac {1}{2}at^2

I'm going to approach this question as simple as possible. I'm assuming you have just started learning the laws of motion or Newtons laws or something like that, so here is how an Australian would answer the question.

Displacement is a vector quantity,( Vector quantity is just stating direction, example: 100m,east.
The formula is Δx=x2-x1
Velocity is the same thing as speed but just stating direction. Its know as a vector quantity as well.
Example: 100ms-1 east.
The formula for average velocity is Vav=Δx/Δt
where Δx means change in displacement and Δt is the change in time.