I am currently using Microsoft windows and I want to shift from windows to Linux, but I have huge data on my hard disk which is placed on other drives other than C drive. Is my data on other drives is safe or not by installing Linux
As long as you don't reformat the other disks, your data won't get affected. Most distros support all of the Windows filesystems by default (NTFS is an odd pickle).
If NTFS is not writable, you need to install
ntfs-3g in order to make the partition writable.
It is safe to install the ubuntu on specified empty drive with out the data lose[where I also suggest that this portal is to coding related question answer so this question seem to better answered in askubuntu.com.
I have installed Ubuntu many times over Windows without problem, which will set your computer up to dual boot windows/Ubuntu. As long as you do not install your new OS over top of the data on the other drives you should have no problem with your data and it will still be available to Windows and will most likely be available to Ubuntu (out of the box).If it is not available to Ubuntu right away installing NTFS-3g will make it available to both OS's.