Pine is generally easier to use for beginners and for simple tasks, whereas Mail is better if you know the commands or want to do more complex tasks or need to clean up large amounts of unwanted mail. There are over 25,000 users on this system and limited disk space.
Disk quotas are the only way to ensure that everyone gets a fair share of the available space.
Your disk quota is the amount of space which you have available for all your mail, programs, web pages, and other files. Once it is full, you can't create any more new files or receive any new mail until you delete enough stuff to make room for the new. This will tell you how many blocks you have allocated and how much you're currently using. A block is 512 bytes or characters. If you are using all or most of your quota, you need to start cleaning up.