Question: How can I plot a Möbius strip? I tried [this one](http://mathworld.wolfram.com/MoebiusStrip.html), but I can't get it to work:

```
ParametricPlot3D[{
    (5 + s*Cos[u/2]) Cos[u],
    (5 + s*Cos[u/2]) Sin[u],
    (s*Sin[u/2])}, {u, -20, 20}, {s, 0, 2 π}]

```

[![my strip](https://i.stack.imgur.com/z3aQV.png)](https://i.stack.imgur.com/z3aQV.png)

Answer: 
Equation taken form the [wiki](https://en.wikipedia.org/wiki/M%C3%B6bius_strip) page 

```
 x[u_, v_] := (1 + (v/2) Cos[u/2]) Cos[u]
 y[u_, v_] := (1 + (v/2) Cos[u/2]) Sin[u]
 z[u_, v_] := (v/2) Sin[u/2]

 plot = ParametricPlot3D[{x[u, v], y[u, v], z[u, v]}, {u, 0, 
    2 Pi}, {v, -1, 1}, Boxed -> False, Axes -> False]

```

[![enter image description here](https://i.stack.imgur.com/KIBPj.jpg)](https://i.stack.imgur.com/KIBPj.jpg)
...and, just for the sake of variation, here is a "minimal" Möbius strip (that is, a [minimal surface](http://mathworld.wolfram.com/MinimalSurface.html) with the topology of a Möbius strip). This example is due to [Meeks](http://dx.doi.org/10.1215/S0012-7094-81-04829-8).

```
ParametricPlot3D[{(r^3 - 1/r^3) Cos[3 θ]/3 + (r^2 + 1/r^2) Cos[2 θ] + (r - 1/r) Cos[θ],
                  (r^3 - 1/r^3) Sin[3 θ]/3 + (r^2 + 1/r^2) Sin[2 θ] + (r - 1/r) Sin[θ],
                  2 (r - 1/r) Sin[θ]}, {r, 1, 4/3}, {θ, -π, π}]

```

![minimal Möbius strip](https://i.stack.imgur.com/3a4Zq.png)