If different, how?
As Colleen said, "center" is the preferred US spelling while "centre" is the preferred UK spelling. As Gabby and Benito indicated, some use "center" to mean a mid point and "centre" to mean an institution but this is not grammatically necessary. While Americans are used to seeing both spellings it is more correct to spell both "center" in the US. Using "centre" in the US could be seen as affected speech; using the British version to try to make an institution appear older or more prestigious. I was rather amused when I started working with my company that they called our server room the "Data Centre." Seems to me an odd juxtaposition. What next? "Ye Olde Data Centre Shoppe Ltd."
According to Grammarist, there is no difference between center and centre when it comes to meaning. The American English prefers to use center while centre is preferred by the varieties of English outside the United States. But there are some people who make distinction between the two words, like some uses center to refer to institution or place while centre refers to the middle point of something. But these are said to be individual preferences only,
Centre in the US started to get used more as a name for structures and commercial retail establishments as a way of making it sound fancy, like "The Centre-At Salisbury" is a Mall in Salisbury, MD. But when used as going to the middle or placing yourself or something in the middle then center is used.
I think "centre" is a place and "center" is the middle of something.. I could be totally wrong though. :P
"Center" is American, "centre" is British (and still used in Canada, as well). They are the same word.
Similar to theater, specter, and liter (all USA) vs. theatre, spectre, and litre (British).
They are the same, "center" is American, "centre" is British. Hope my answer helps =D
LOL I was just gonna say "Centre" is Canadian. You know how I make fun of Canadia.
You love us, Ericson ... you know you do :P
Thanks everyone! That helped me :)