T.Code FB03 & SQ01

Hi Seniors,

Can anybody tellme what is the use of FB03 & SQ01 with detailed information please.

If i didnt mistake SQ01 is being used by ABAP Consultant not FICO Consultant please give me some more detail information pertaining SQ01.

Awaiting for your reply & points will be assigned.

Thanks & Regards,

KUMAR.B