Hello, So I will be purchasing some sort of external hard drive soon (be it a regular external or an enclosure & separate drive), and I was looking for suggestions. I realize that there are a lot of these threads but I was hoping to get some personal suggestions or recommendations, plus I have a couple of important questions. I was originally set on a Western Digital Elements SE (500 GB) but I realized that it only has a 1 year warranty, which doesn't seem too good. Also, I was wondering something that may be quite important... What does Time Machine actually do? I intend to use it to back up my MacBook Pro. The reason I am asking is I am trying to figure out whether it is wishful thinking or not to get an external back up that is equal in size to my internal hard drive. Should I be shooting for a 750 GB or 1 TB external drive, given that I have a 500 GB internal? Granted, I will only let the internal get to around 80% full (400/500 GB), so would I be alright with a 500 GB external? Will Time Machine be creating some sort of excess amount of storage space to do whatever it does? Would it be ideal to go for an enclosure & separate drive over a regular external hard drive, or should I just get the latter with a solid 3-year+ warranty? This is confusing because when I looked up preferences towards externals, a majority of the replies were concerned with getting a drive with a solid warranty (3-5+ years). However, most of these best selling Seagate and Western Digital Drives on Newegg have a 1 year warranty. Any insight? Thank you.