Perimeter
 

A perimeter is a path that encompasses/surrounds a two-dimensional shape.
The term may be used either for the path, or its length—in one dimension.
It can be thought of as the length of the outline of a shape.
The perimeter of a circle or ellipse is called its circumference.

Calculating the perimeter has several practical applications.
A calculated perimeter is the length of fence required to surround a yard or garden.
The perimeter of a wheel/circle (its circumference) describes
how far it will roll in one revolution.
Similarly, the amount of string wound around a spool is related to the spool's perimeter;
if the length of the string was exact, it would equal the perimeter.

Perimeter Definition

Perimeter is the distance around a two-dimensional object. You can also measure the perimeter of
three-dimensional objects like houses, stadiums, buildings and similar shapes.

Perimeter is the sum of the measure of every side of a 2D shape, or the sum of
the measure of every side of a 3D shape measuring on the ground or floor.

Round shapes (ovals, circles, ellipses and such) have perimeter, but we
almost always call that measure circumference.

Perimeter is always a linear measure. Use the same units given for each side,
like mm, foot, and so on.

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