Mathematica can plot parametric functions in both two and three dimensions. Use a parametric plot when you can express the

and

or

,

, and

coordinates at each point on your curve as a function of one or more parameters.
Plot the parametric curve

where the parameter

varies from

to

:
You can plot two parametric curves by putting them in a list:
Plot more parametric curves by adding them to the list:
Use
ParametricPlot3D to plot the surface defined by

:
Plot the parametric curve

in 3D: