Can you please explain Einstein’s Special Theory of Relativity?

Question: Can you please explain Einstein's Special Theory of Relativity?
- Keywords:
  einstein,
  theory of relativity
Asked by anon-18007 to Cathal, Daphne, Darren, Jon, Katherine on 14 Mar 2012.
- Katherine Haxton answered on 14 Mar 2012:
  
  I used to be able to when I did physics but I’ve forgotten now! You could try searching the internet 😉

Question: Can you please explain Einstein's Special Theory of Relativity?