CRON to schedule batch class to run everyday at 10PM

For daily 10 PM

0 0 22 * * ? *

first 0 for seconds

second 0 for min

third 22 for hours i.e. 10 PM

you can use http://www.cronmaker.com/ for generating cron expression

for more detail check Apex Scheduler

Adding an answer because I always end up here and then have to look through the docs to remember the syntax:

Cron Format:

second minute hour day_of_month month day_of_week optional_year 

Format Values

second:        0 (this doesn't actually do anything)
minute:        0–59
hour:          0-23
day_of_month:  1-31 - * ? / L W
month:         1-12 JAN-DEC , - * /
day_of_week:   1-7 SUN-SAT , - * ? / L #
optional_year: null or 1970–2099 , - * /


Character   Description
,           Delimits values. Example: JAN, MAR, APR
-           Specifies a range. Example: JAN-MAR
*           Specifies all values
?           Specifies no specific value
/           Specifies increments. Example: Day_of_month = 1/5, the will run every fifth day of the month, starting on the first of the month.
L           Specifies the end of a range (last). See docs for more details
W           Specifies the nearest weekday of the given day. Example: 20W. If 20th is a Saturday, the class runs on the 19th
#           Specifies the nth day of the month, in the format weekday#day_of_month. Example: 2#2 means the class runs on the second Monday of every month.

Examples:

Expression          Description
0 0 13 * * ?        Class runs every day at 1 PM.
0 0 22 ? * 6L       Class runs the last Friday of every month at 10 PM.
0 0 10 ? * MON-FRI  Class runs Monday through Friday at 10 AM.
0 0 20 * * ? 2010   Class runs every day at 8 PM during the year 2010.

Apex Code:

String jobID = System.schedule('My Scheduable', '0 0 22 * * ? *' , new MyScheduable());