1. A function can have return statement where as a procedure cannot have a return statement.
>>    A function always has a return value. The "value" have be one of many things including pl/sql tables, ref cursors etc.
2. A procedure can be executed separately from SQL and also can be invoked from some other procedures or functions where as a function can only be invoked from a function or a procedure.
>>    A function can be called from anonomous pl/sql - the return value needs somewhere to go...
exec dbms_output.put_line(my_funct());
3. A function can be used in DML where as a procedure cannot be invoked from a DML.
>>    Triggers can call functions. procedures can't be called directly in sql statements. Procedures can be called from simple wrapper functions.
4. We cannot use DDL in a function where as in procedure it is possible using dynamic SQL package.
>>    dml can be used in functions and procedures
5. A procedure can be either stored procedure or an anonymous where as a function cannot be anonymous.
>>    anonomous pl/sql is not usually refered to as a procedure in Oracle.
6. We cannot use a Transaction control language in a function where as in Procedures we can use TCL.
>>    Not true in general. (in any case, a wrapper function can call procedures so anything a procedure and do a function can do)
7. Functions can also have IN and OUT parameters.
>>    yes
8. Functions are used for computations where as procedures can be used for performing business logic.
>>    functions and procedures can be used for whatever you choose.