Time limit

Hi
i am using routeros 3.3 version, I am new to this.
I just wanted to know that can i set time limit for my work stations.
Example: Like morning 11 to 12 i need to block some websites.
can anyone help me

regards
suresh

use the “System Scheduler” to enable or disable certain configuration rules at different times of day.
http://wiki.mikrotik.com/wiki/Manual:System/Scheduler