A perimeter is a curve or boundary enclosing an area, or the length of such a boundary.
A parameter is a measurable factor that determines the specific nature or behavior of a system. In mathematics, a parameter is a constant in a function that can be varied to generate a family of curves or surfaces with the same general form. In the equation y=ax2+bx+c, a, b, and c are parameters. Similarly, a parameter can be a variable in a statistical distribution, or an argument in a computer program.