Now a days, disks are very secure, and it is not easy to find bad blocks on them, anyway, if the information you are going to save in a given disk, it might be a good idea to check the disk for bad blocks first.

Linux has a good tool for this: badblocks

It is really easy to use, first, be sure the disk you are trying to check for bad blocks with badblocks command is not mounted, then run

badblocks -n -s /dev/sdX


badblocks -n -s /dev/hdX

Where the X is the partition of the disk you want to look into for bad blocks.

Important Note: read the badblocks man page, before use it.