Both of them will print what you want at the coordinates you give but the diference is that the TEXT command will start at the coordinates and start writing it to the screen from that spot, and CENTER TEXT will print the text and the center of the text will be the coordinates.
Example. If the x coordinate is 100 it would look something like this.
text:
__________________________________The text starts at the coordinates and writes across.
center text:
______________Whatever the text is it is centered on the coordinates.
Hope this helped
position object MyFoot,object postion x(yourAss),object position y(yourAss),object position z(yourAss)