Cron works by running a file at certain timed intervals. Generally these are set up at about 10 minute intervals by us for Interspire Email Marketer but they can be set to anything you like.
When you use cron to send your email campaigns Interspire Email Marketer will make a list of when you want to send that email. Each time cron runs the file Interspire Email Marketer will check these scheduled emails and if there is one (or more) there that are due to be sent it will start to send.
