Instant Messaging Spam
Instant Messaging spam uses of instant messaging systems, such as ICQ, AOL Instant Messenger or Windows Live Messenger to send spam. Many IM systems offer a user directory that allows people to gather the information, sign on to the system, and send unsolicited messages. To send instant messages to millions of users requires scriptable software and the recipients' IM usernames to bombard them with advertising.
Chat Spam
Chat spam consists of repeating the same word or sentence many times to get attention or to interfere with normal operations. It is generally considered very rude and may lead to swift exclusion of the user from the used chat service by the owners or moderators.
Mobile Phone Spam
Mobile phone spam is directed at the text messaging service of a mobile phone. This can be especially irritating to customers not only for the inconvenience but also because of the fee they may be charged per text message received in some markets.
Spam Targeting Search Engines (Spamdexing)
Spamdexing refers to the practice on the web of modifying web pages to increase the chances of them being placed high on search engines. These sites use "black hat search engine optimization techniques" to unfairly increase their rank in search engines. Many modern search engines try to exclude web pages utilizing spamdexing tactics.
Blog, Wiki, and Guestbook Spam
Blog spam , or "blam" for short, is spamming on weblogs. This type of spam takes advantage of the open nature of comments on blogs by repeatedly placing comments that provide nothing more than a link to the spammer's site. Similar attacks are often performed against wikis and guestbooks, which also accept user contributions.
Spam Targeting Video Sharing Sites
Video sharing sites, such as YouTube , are now being frequently targeted by spammers. The most common technique involves people (or spambots) posting links to sites on the comments section of random videos or people's profiles.
Noncommercial spam
E-mail and other forms of spamming have been used for purposes other than advertisements. For example, a number of evangelists have spammed people with preaching messages.