1 bsfilter is a spam filter using Bayesian(statistical) algorithm.
3 - a filter which distinguishes spam and non-spam mail
4 - support mails written in English and Japanese language
6 - support 3 methods for access
7 -- traditional unix-style filter. study and judge local files or pipe
8 -- IMAP. study and judge mails in an IMAP server
9 -- POP proxy. run between POP server and MUA
10 - distributed under GPL