Translation of text or messages provides a message that is more reliably or efficiently analyzed for purposes as, for example, to detect spam in email messages. One translation process takes into account statistics of erroneous and intentional misspellings. Another process identifies and removes characters or character codes that do not generate visible symbols in a message displayed to a user. Another process detects symbols such as periods, commas, dashes, etc., interspersed in text such that the symbols do not unduly interfere with, or prevent, a user from perceiving a spam message. Another process can detect use of foreign language symbols and terms. Still other processes and techniques are presented to counter obfuscating spammer tactics and to provide for efficient and accurate analysis of message content. Groups of similar content items (e.g., words, phrases, images, ASCII text, etc.) are correlated and analysis can proceed after substitution of items in the group with other items in the group so that a more accurate detection of "sameness" of content can be achieved. Dictionaries are used for spam or ham words or phrases. Other features are described.