A cron expression consists of five individual parts (That is the basic version. Some cron expressions support additional values).
In addition to the above values the following characters can be used.
15 1 * * * every day at 1:15 am
0 8-17 1-5 * * Monday thru Friday, once every hour between 8am and 5:59pm
0 5 1 */3 * at 5am on the first day of every third month of the year (Jan, Apr, Jul, Oct)
0 0 1 1 * start of the year
*/5 3-14 * * 6 every five minutes between 3am and 2:59pm only on a Saturday
Cron expressions are widely used. To get more detailed information those links might be helpful
Part
Allowed Values
Minutes
0-59
Hours
0-23
Day of month
1-31
Month
1-12
Day of week
0-6 (0 = Sun, 1 = Mon, ...)
Character
Meaning
*
Any value e.g. * as the value for Hour will select all the possible values 0,1,2,..,23 "every hour".
,
value list separator e.g. 0,30 as the value for Minute will select 0 and 30 "every half hour".
-
Range of values e.g. 1-5 as the value for Day of week will select Monday thru Friday
/
step values e.g. */3 as the value for Month will select Jan, Apr, Jul, Oct. Writing "1,4,7,10" would yield the same result.