At

From Linux 101, The beginner's guide to all things Linux.

at is used to schedule a single task. If you want a task to be run at certain times indefinitely, you should use cron.

To schedule a task, execute:

at <time>

To schedule a command at 7:00 PM, use:

at 7:00 pm

Then type the commands you want to be executed and exit with CTRL-D (meaning EOF, or end of file). You can also pass the file to execute using the -f option.

To list the current scheduled jobs:

atq

To remove a job:

atrm <job #>

You can also do some things like specify executing the command a number of minutes, hours, days, or weeks by doing something like:

at now + 3 hours

Further examples are given in man at.