Difference between BIS and BES

What is BIS?
BIS stands for BlackBerry Internet Service. It gives your BlackBerry access to the Internet. BIS allows Blackberry users to access the Internet and POP3/IMAP/Outlook Web Access email accounts such as Gmail, Hotmail etc. The service is usually provisioned through your mobile phone service provider. This service uses RIM's proprietary push technology which allows real-time access of email.

What is BES?
BES stands for BlackBerry Enterprise Server. It gives your BlackBerry access to a corporate intranet. The intranet is the private, internal, network within a company.BES, connects to messaging and collaboration software (Microsoft Exchange, Lotus Domino, Novell GroupWise) on enterprise networks to redirect emails and synchronize [Personal information manager | PIM] information between desktop and mobile software.