External hard drives are best used for large amounts of storage, especially when the number of DVDs you would require is prohibitive. Large external disc drives can hold dozens, even 1-2 hundred captured video files in edit quality format. Smaller formats will allow even more videos to be stored.
The major advantage to external hard disc storage is that a very large amount of audio and video can be stored in a small location, it is portable between computers.
Disadvantages are that a very large amount of video data is at risk in case of an accident, loss, or failure. It is highly recommended that at least one backup is made of every external drive.