Difference between Netbackup and Backup Exec

My experience with data backups so far has been with simple methods for small networks mostly workgroup. I have used programs like SecondCopy2000, Corbian Backup, and batch files. I want to know more about enterprise level backup application packages. I have heard about Backup Exec because I have supported networks that use it but personally I have never managed it. Today, I heard about Netbackup. Because both are sold by Symantec, it begs the question: what is the difference? Obviously these two programs are not competitors, at least not of a one-to-one kind like Office and OpenOffice. The best answer I have found so far was this little snippet:

Netbackup is more expensive than Backup Exec. What do you get for your money?
The most obvious difference between Netbackup and Backup Exec, is that Netbackup is designed for BIG business. Backup Exec is aimed more at small and medium business. Over recent years, Backup Exec has gained features to make it more scalable and manageable, and improve its functionality. Specific example of this are the Central Admin Server Option, and the addition of encryption capabilities. Recently Netbackup has been adding packages (the non-Enterprise versions) which target small and medium business.