Why BAPI rather than RFC ?

Hi.

I got an idea on BAPI and RFC but I am bit confused at this point.

BAPI can be used to access the SAP data from other technologies because we place the BAPI in BOR. But the same work can be done by RFC also.Both are same right.Then why should we use BAPI ? What can't be achieved by RFC and can be only by BAPI ?

Please don't share BAPI vs RFC. Provide why BAPI and why don't RFC ?

Thanks in advance.

Pradeepkumar Jayanthi