Please help me..... its urgent

Hi everyone,
Please let me know is there any difference between Unix shell script and AIX shell script. If it's so please let me know what is the difference.
PLease also tell me if scripts are working fine in Unix, will the same scripts work for AIX...PLease help me,......

You didnot specify about the other distro that you are using apart from your specification of IBM-AIX,

then its your shell that you use,
same ksh on either of the boxes should be the same.

May be for some difference. I am not sure of them.