In a former article I’ve talked about the commands cron and crontab that are the standard way to schedule recurring things on a Gnu/Linux system.
But sometimes you need to do one thing at a specific date and time for just one time, and for these tasks the best option is to use
at, another way to use
at is to run a command later when the computer won’t be busy.
Or another reason could be that you want to run a command that requires a lot of time to end and you have to disconnect from that server,
at could be used in this situation, but for these task i suggest to take a look at the articles on how to run commands on background and the utility