Making up for your space needs, the 1TB external hard drive is a decent amount of space to add onto your laptop. It could do well as a drive you work of, or for a backup drive to store important templates or documents. Also, good as external hard drives are easily portable; this does mean that they would be easy to misplace. With slight variations in internal build, the one you chose is more about what you are looking for it to do and the budget you have in mind. The newer Solid State Drives cost a bit more and are faster in performance.
External hard drive convenience
Ample space to last a good while a 1TB external hard drive would work well as a backup storage drive or if you want to add space to your laptop in case you have larger files you work on; like many video formats. In the case of video, a 1TB external drive is still just on the cusp of being enough to not overload your laptop so when you work the laptop isn't sluggish.
Advantages and connectivity
Backing up your files regularly is smart as there are so many chances of a laptop or desktop crashing, but losing files would definitely feel worse than the crash itself. The advantage with these drives is that they are also quite a portable size so storing it in a drawer or safe wouldn't take up too much space either. As for connectivity most of these external hard drives use USB or FireWire, there are some that use eSATA and WiFi too but that is more specific a buy. The WiFi one would need external power to run the wireless systems that link it to the computer. With various transfer rates, one can check to see what their speed needs are when working or backing up.
The different types
1TB drives are available as Solid State Drives (SSD) or the older HDD ones, SSD is faster and has less wear and tear over time as it doesn't have moving parts. SSD uses electronic circuits to write and retrieve information so the lack of any movement over its written area makes it faster as well. This is based on the Flash Memory tech that is also used in our RAM chips which process our computers general running.
Well known brands
A lot of brands make 1TB external hard drives but the more common and market-tested brands include Western Digital, CalDigit, Seagate, LaCie, ADATA and Samsung among others.