You've got to admit that the concept of putting the Sabbath to Saturday makes sense -- after all, God rested on the seventh day, and Saturday is the seventh day of the week.
Anyway, that having been said, not all religions observe the Sabbath on the same day. I'm no religion scholar, but here is what I know:
- Most Christian Denomiations - Sunday
- Jewish - Sundown Friday to Sundown Saturday (Thanks for calling me on this, Jurph)
- Seventh-Day Adventist - Saturday
- LDS (Mormon) - Could use some explaination...
Althought he LDS people generally as a whole will observe the Sabbath on Sunday, this is not rigid. The Beliefs of the LDS church are that the day of the Sabbath is not (and it not required to be) rigidly defined; An example is the BYU Extension in Israel; Since the Jewish faith is the majority there, most of Israel shuts down during the day on Saturday and so most students and staff at the BYU Israel Centre observe Saturday as their Sabbath as well.
...I know I've missed many, so please, add them!