You know what they say, it is better to err in the side of caution when dealing with email spam by deleting it right away without opening it.  However, curiosity can prevail over many people that is why spammers still achieve a certain degree of success in spite of repeated warnings against them.  They know they will not get 100% of their target but any small percentage can amount to a grand scale when taken collectively.  Spammers are known to do their thing over and over. 

The mildest effect of receiving and opening a spam email is probably to read ads about Viagra or sexually-explicit products.  However, many spam emails are sent with a more vicious companion, a malware that can paralyze a whole computer system.  It can start to freeze before if finally crashes.

Spam email is also known as junk email.  This is in reference to its contents which represent no value to the recipients who did not seek the information offered by the mail.  Unsolicited and coming in bulk often characterizes the nature of spam email.  Email addresses are obtained by spammers from websites, newsgroups, chat rooms, and even viruses which have been sent for such purpose.   

 

Phishing is another major concern in relation to email spam.  An email can look genuine in all aspects and succeed in obtaining personal information from the addressee.  In phishing, a person transacts with a site thinking that it is the legal site of a bank or any other legitimate organization.  The danger in having this information in the hands of scammers and phishers is quite obvious.  So when in doubt, resist the urge to engage in online adventurism and err in the side of caution.