Fcron is a scheduler. It aims at replacing Vixie Cron, so it implements most
of its functionalities.

But contrary to Vixie Cron, fcron does not need your system to be up 7 days
a week, 24 hours a day : it also works well with systems which are
not running neither all the time nor regularly (contrary to anacrontab).

In other words, fcron does both the job of Vixie Cron and anacron, but does
even more and better :)) ...