is a very good tool to have in your backup arsenal.
Unfortunately, any backup that is made to an external drive is also subject to the drive failing.
Consider also a program like SuperDuper or Carbon Copy Cloner, to make a copy of the hard drive and consider putting those onto optical media and storing them at the bank.
That said, Time Machine has saved my butt on three different occasions when my iMac internal hard drive crashed.
Replace the drive, install OS X, and restore from a Time Machine backup. Like it never even happened!
Partitioning the drive does not give you any extra protection in case of failure, it's all the same disk, so you could forgo the partitioning.
Time Machine keeps its backups neatly inside a Folder called xxxbackup, where xxx is the name of your computer, so you can use the rest of the space for other things without worrying about running out of space.
I have a new Seagate Backup Plus 3TB ("For PC and Mac") that I want to connect to my MacBook (2.4GHz Intel Core 2 duo; OS10.6.8). I would like to use it for regular backup, photos (many lge RAW files), music (not a lge collection but growing); storage of pdf and wp files use for several ongoing research projects; and storage of movie projects (not many but could expand). I partitioned my last 160 GB HD for backup and storage but later found that I hadn't allowed enough space for the backup. I'd like to avoid that this time. I also have a pile of thumb drives with content that I would like to get organized.
I would appreciate suggestions regarding formatting and partitioning as well as about backup software. (In the past I used Backup w/ iDisk. Is Time Machine the best option?) It is highly unlikely that I would ever need to connect to a PC.