Difference between insert and Database.insert() 

Database.insert() :

                             Using the  Database.insert()  we can specify whether or not to allow for partial record processing if errors are encountered .

                              It means even though errors are present while doing insert/update/delete operation,if we use Database methods, process will continue .

insert :

           Using the Insert statement we can not specify whether or not to allow for partial record processing if errors are encountered .

              It means if errors are present while doing insert/update/delete operation,the process will get stopped and error is thrown away.