The first thing to know is that there are two main types of hard drive. There's IDE (the older type) and SATA (AKA: Serial ATA). Second thing to know is that there are two main sizes of hard drive (AKA: form factor). There's 2.5" which is usually used in laptops and there's 3.5" which is usually found in desktop PCs. 3.5" hard drives are usually more stable and less fragile. Thirdly it's good to know that you can purchase both internal and external hard drives... however you'll usually find that an external hard drive is in fact an internal hard drive put into a hard drive enclosure which has a USB 1.0/2.0 or Firewire connection. If you've got a number of hard drives, or are planning to buy a few, you may be financially better off purchasing internal hard drives and one enclosure or docking station, that way you're not paying for the enclosure and the labour of putting it in each time in with the purchase price! This article should help you to understand some of your options and help point your purchasing decision in the right direction...

USB 2.0 Enclosure for SATA HDD

This first enclosure is for a 2.5" SATA hard drive up to 500GB and the second is for a 3.5" SATA hard drive up to 750GB. You unscrew the enclosure, connect your hard drive to the cables inside and resecure the unit. You then plug in the provided USB cable to the enclosure and your computer. Windows 2000, Windows XP and Windows Vista operating systems should then automatically recognise the unit and your hard drive should appear on the hard drive list within a couple of seconds ready to be used just as your other hard drives which are inside your computer are.

USB 2.0 Docking Station for 2.5" and 3.5" SATA HDD

A Docking Station is great if you've got a number of SATA hard drives, instead of buying lots of enclosures or purchasing one enclosure and having to keep unscrewing the lid and disconnecting the hard drive each time, you simply purchase one docking station and just swap each hard drive over using the eject button!

This first docking station can take both 2.5" and 3.5" SATA hard drives. The second can again take both 2.5" and 3.5", but can also be used as a card reader and USB hub.

Ethernet HDD (NAS - Network Attached Storage)

Ethernet hard drives plug into your router instead of your computer. They use an ethernet cable to connect to the router instead of a USB cable or firewire cable which would plug directly into your computer. Having a NAS (Network Attached Storage drive) plugged into your router and configured means that everyone on your network can access the storeage space. So if you need to get to the same files from different computers or you want to back up loads of computers to the same hard drive, NAS is often the solution. (It's worth noting that most domestic NAS drives don't have any server software so each file can only be opened by one computer at a time - so if two of you want to look at the same photo or read the same PDF one of you will have to wait). The first unit here converts a USB hard drive enclosure into a NAS drive. The second is a NAS unit with a 500GB hard drive inside. The third is a NAS unit with a 1TB (1000GB) hard drive inside. The last unit is a NAS enclosure which can take up to 4 individual SATA hard drives.

SATA Hard drives

Here is a selection of SATA hard drives which have fast spin speeds and large caches for quick data recall and transfer.

Firstly a 160GB 2.5" hard drive. Then a 250GB 2.5" hard drive. Then a 500GB 3.5" hard drive and finally a 1TB (1000GB) 3.5" hard drive.

Extras

Firstly we have an IDE to SATA adaptor / SATA to IDE adaptor. This allows you to convert SATA drives to IDE and convert IDE drives to SATA drives. Then we have a wireless ADSL2 router followed by a wireless cable router, and then a surge protected plug board with power, phone and ethernet sockets.