Migrating from Windows XP to Windows Vista

Hello Everybody,
I am using a computer in my home that runs on windows XP home OS. I found that VISTA has got more enhanced features compared to XP and want to upgrade. Please tell me the process of upgrading and the requirements needed.
Also please tell me will there be any data loss or not. Kindly provide me with this info so that I can start my upgrade process.
Thanks for the help.
