E-mail whitelists are the ultimate in spam protection, and go beyond the safeguards used by spam filters and spam blockers to almost completely eliminate the possibility of receiving spam. Whitelists work like fortresses to completely protect the user against invasion.
Before e-mail from a new address can be allowed into the inbox, the user must answer questions or type in a partially obscured code that is recognizable on normal computers, but cannot be detected by the kind of software spammers often use.
The result is a combination of computer technology and a users own judgement to decide which users will be allowed to send e-mail to the account or not. Once the potential sender is approved, he or she can send e-mail to the account without having to re-register.
Many people prefer whitelists to spam filters and spam blockers. Spam filters are often free with any e-mail provider, and use probability formulas to calculate the likelihood that e-mails containing certain keywords will be spam.
The problem with this approach is that many spammers can get around these filters by using words not associated with spam and by intentionally misspelling...