circle | x(t) = a cos(t) y(t) = a sin(t) ellipse | x(t) = a cos(t) y(t) = b sin(t) hyperbola | x(t) = a sec(t) y(t) = b tan(t) parabola | x(t) = 2 a t y(t) = a t^2 rectangular hyperbola | x(t) = a sec(t) y(t) = a tan(t)

circle | x^2 + y^2 = a^2 ellipse | x^2/a^2 + y^2/b^2 = 1 hyperbola | x^2/a^2 - y^2/b^2 = 1 parabola | y = x^2/(4 a) rectangular hyperbola | x^2 - y^2 = a^2

circle | r(θ) = a ellipse | r(θ) = (a b)/sqrt((b^2 - a^2) cos^2(θ) + a^2) hyperbola | r(θ) = (a b)/sqrt(b^2 cos^2(θ) - a^2 sin^2(θ)) parabola | r(θ) = 4 a tan(θ) sec(θ) rectangular hyperbola | r(θ) = a sqrt(sec(2 θ))