If you are using Mac at home and you need to have a parental control over your system, then it is almost all kept ready for you. The Parental Controlling features in Mac has all the required controlling options to block the content and in its applications for a specific user from using or viewing it. The Parental Control feature here will allow you to control the incoming as well as the outgoing emails, and even the contacts of iChat.
There is also an option to use Parental Controls where you can set the time limits on the usage of your computer, whether it is the number of hours or the slot of hours of the day when the computer will be used by your child. Moreover the Parental Control system in Mac maintains a log which keeps you informed about the way your Mac system is being used and even by whom it is being used.
To Launch the Parental Control you have to "Open the System Preferences' by clicking on its icon in the Dock, or you can also select the 'System Preferences' from the Apple menu. There you will find the 'System' section in the section of System Preferences, so click on the 'Parental Controls' icon and the Parental Control preferences window will open.Once you get into that page you have to Click on the lock icon placed in the bottom left-hand corner. There you would be asked to fill in the fields of administrator user name and password before you can continue.
Apart from these it is always advisable that you keep changing the username passwords in regular intervals. Also it goes without saying that don't keep a file that contains those username and password detail which is witin your children's reach.