Things are harder to do in space. Weightlessness can turn the most mundane task into a problem that can take hundreds of engineer hours to solve. Sleeping is more difficult and using the bathroom requires a lot more equipment and care. Even drinking a cup of coffee in the morning needs a specially engineered cup.
Here's a great video showing how it works.
Are you on Twitter? Follow me (@sheagunther) there, I give good tweets.
And if you really like my writing, you can join my Facebook page.