Question about firewire/eSATA/USB/expresscard

[Ying]

I've searched around for the differences between these three connections and I just ended up confusing myself. Can someone explain what is the difference between firewire/eSATA/USB/expresscard, besides their speed? My laptop (Sony VAIO) has 3 USB (not sure which, I'm guessing USB 2.0) ports, 1 "expresscard" slot, and 1 "eSATA" slot. I'm wondering:
- Can firewire be connected to the expresscard or eSATA slots?
- My prof said that I need to get a "firewire 800 7200rpm USB 2.0 1TB external hard drive with its own power supply" for basic video editing, should I get that or get a drive that uses eSATA/USB 3.0? Can USB 3.0 external drive be connected to my USB 2.0 port?
- Can the same external drive be connected to both laptop and desktop (iMac)? I use a windows laptop, while my school uses a desktop iMac
What is mant by "firewire 800 USB 2.0"? Aren't they different connections? Please recommend what I should get, I don't want to spend too much as I'm only going to use it a few times during class and never use it again. I also want to make sure I can actually use it on my laptop, and not something that can only be connected to the school's computer because that would be really a waste.
Thanks.

[Ying]

Help please

[IAntDemo]

usb 3.0 will be backwards compatible so I'm sure yes it will connect

I'm not 100% sure on the others, altho when you connect the harddrive to windows it will show diffirent file formats to a mac .. I'm so sure all this will get abit to confusing.. I'm not sure if when you save on an mac a photo image as .png .. does it save as .png from mac? windows does.. if it does then I don't see why not.

I'm sorry if this isn't much help at all

[Dngrsone]

I have an eSATA port on my laptop, it doubled as an USB port as well.

With that said, I had problems getting eSATA working well, and the speed on my computer was no different between SATA and USB.

I have firewire ports, too, but nothing I use supports firewire, so no personal data on that.