what is a mobious strirp it was mentioned in the big bang theory?

Question: what is a mobious strirp it was mentioned in the big bang theory?
- Keywords:
  colour,
  sight,
  television
Asked by crispysheldon to Angela, Gopal, Hannah, Becky, Vince on 24 Jun 2013.
- Gopal Ramchurn answered on 24 Jun 2013:
  
  I’m not an expert but from what I read, a mobius strip is a surface with only one side – you can create one by taking a strip of paper, twisting it and glueing the end bits of the strip.
- Hannah Little answered on 25 Jun 2013:
  
  Simon Singh and his wife have mobius strip wedding rings, how geeky is that?

Question: what is a mobious strirp it was mentioned in the big bang theory?