My Mac OS X & different ways to back it up

We humans need to act like ants, which are the hardest working creatures on the planet. Like ants collect their food stuff for the winter season, we too can back-up our entire hard drive data and contents to overcome a near future obstacle. These uninvited obstacles may be in the form of hard drive failures, data corruption, system inaccessibility, or theft. Although I don't have the exact figures of such obstacles but I could only estimates that thousands of Mac users go through the pain of data loss due to sudden malfunction of the Mac machine, software gone bad and theft. Such circumstances may not be under control of any user but we can act beforehand to at least ensure the content of the hard drive remains accessible by implementing a back-up plan.

Components of the back-up plan include two basic requirements:

• The system hard drive (source) and,
• an external hard drive (destination),
• Third back-up process may include the use of online storage Medias which are becoming popular day-by-day.

External hard drives are the accessories which are most used by the users, after all who doesn’t require having additional storage capacity. 

1.Imaging the hard drive: With the help of a non-Apple utility, we can choose to create an image file of the drive (important data). Once the imaging is made it may be stored on the source itself. However how wise it would be store on the same system taking the inaccessibility of the Mac on account. This can be done by saving the back-up on an external hard drive and should be done on weekly basis.  

Stellar Drive Clone 2.0: Ready to create an image file of hard drive or volume

(The chosen drive is imaged to the user's location)

2. Cloning the hard drive: Another activity you could do in place of imaging is cloning the source to a large destination (A destination drive larger than source is always required to make a clone). What is good about the cloning is it creates a similar copy of the source hard drive which is in the ready to use form.

Take Note that: Cloning erases all the content of the destination drive. If destination > source drive then you can also expand the volumes located on destination drive. Cloning creates a bootable DVD for the system helpful to boot the Mac if inaccessible. 

3. Time-Machine backup: It’s simple to do by connecting an equal or bigger external hard drive to the Mac system. Making way through System Preferences<<Time Machine, double click to launch it and switch the time machine ON. See the 'Select Disk' option, you need to click and select the connected external drive. All done, only the check box located at below needs to be clicked. 

Wikipedia: Time-Machine in action can be found in the Mac 10.5 and above versions. It creates incremental backup that can be restored at backward date.