Hi DBAs, Can anybody plz point the exact difference between GUEST/ORACLE and APPLSYSPUB/PUB.. and where does APPLSYSPUB/PUB comes into picture... I guess when User types his Username Password in login window and clicks submit button..Then Webserver checks that username and passwords need to authenticate against database *FND_USER * table..So GUEST/USER comes into picture...but Where does APPLSYSPUB/PUB comes into picture... Plz advice me......... Sreenivash.