Publisher Summary This chapter discusses some of the most common methods of sending spam. They range from the traditional (the first methods used to send spam) to the innovative (the cutting edge techniques that spammers are creating and perfecting today). The chapter is supported by uniform resource locators (URLs), screen shots, and as much information as possible, and also includes the author's own personal comments on the methods and his success using them. It covers the core technology used behind sending spam from the most popular methods to the oldest methods. Proxy servers are the most widely used method of sending spam. The proxy server is a server used within a network that other computers use as a gateway to the Internet. The use of e-mail relays was the first real spamming method used on the Internet. An e-mail relay is much like a proxy server but is used only for simple mail transfer protocol (SMTP). Botnets are armies of compromised machines (also known as zombies). Controlled by a single master, these zombies can do anything from performing a distributed DOS to sending spam.