This document summarizes spamming and spam filtering techniques. It discusses how spamming works by sending unsolicited messages from individual email accounts or open relay servers. It then outlines various spam filtering methods like blacklist, whitelist, content-based filters that analyze words or use heuristics. The document implements a simple spam sending program and shows how gmail and outlook spam filters work. It concludes by discussing the effectiveness of different filtering approaches and references further reading on minimizing spam effects.