Simple triggers vs Cron triggers

Simple triggers	Cron triggers
SimpleTrigger is useful for jobs that you want to execute exactly once at a specific time, optionally followed by repeated execution at a specific interval.	CronTrigger is much different in that it is for jobs that are inherently recurring on some calendar based schedule.
Simple Triggers allow you to set basic start and end times with repeat intervals	Cron Triggers allow you to set a more complex schedule using a cron expression.
A Simple Trigger allows you to specify a start time and end time for the Job to run. You can also set a repeat interval, which will cause the Job to run multiple times at the specified interval	A Cron Trigger allows you to specify a more complex schedule using a cron expression. A cron expression consists of 6 fields that define the time and date when the Job should be executed.