What's the difference between JMS and Java Mail API?
JMS is a standard that lets Java applications access MOM (message-oriented middleware) systems such as IBM MQSeries, SonicMQ, Softwired iBus, TIBCO, etc.
JavaMail is a standard that lets Java applications access e-mail servers such as MS Exchange, Unix sendmail, etc.
In summary: JMS is for high-performance, reliable application-to-application messaging. JavaMail is for writing Java applications that send and receive e-mail.