I believe I lack a great deal in my understanding of parameterisation.
The following vector-valued function $f(t) = (t\cos(t), t\sin(t))$ is said to be a parametric function but I don't understand why? Is it because it only has a one-dimensional input?
Secondly, why are parametric functions used so much in the multivariable world? What's the big deal? Can't we just use non-parametric functions?