Sending messages requires you to assemble an instance of Mail and feeding it to the sendMessage() operation.

BRIDGE > Sending Messages > jmail_send.png

BRIDGE > Sending Messages > jmail_sendparams.png

Operations

sendMessage

sendPgpMessage

Types

Mail

Attachment

Adding inline images to HTML emails is an art form. Be prepared to see different results depending on the client application receiving your message. Make sure to test your HTML code thoroughly to get good results.
Also, sending large images inline is considered bad style as it blows up message size considerably and could be replaced with links to online locations of the image (e.g. a CDN or publicly accessible web server).