so many things to think about...I really appreciate the help everyone. this probably is a stupid question but since some of you don't rely on a web based storage option what is really the difference between a personal at home cloud storage option (like WD My Cloud) and an external hard drive??
An external hard drive connects to your computer via a high-speed data channel, like the common USB 3, or some similar technology. *Internal* hard drives typically use an even faster data bus.
How much of a difference the speed of a data channel makes depends on the speed of the hard drive itself. The all-electronic solid state drives, which are considerably faster than the old mechanical hard drives, can really take advantage of faster data channels.
The WD My Cloud connects to your network via an Ethernet cable, and typically the My Cloud is connected to an Ethernet switch, and not directly to the computer. For example, you might plug a My Cloud into your WiFi router. The typical gigabit speeds offered by these devices are slower than the data channels for a directly connected external hard drive. Also, you have to make sure that everything in your network between the computer and My Cloud can also support the higher gigabit speeds, otherwise you'll get considerably slower speeds.
The advantage of a network connected solution, like the My Cloud, is that you can place the device far away from your computer, and it does not need to be physically attached to it. For example, you can back up the files from a laptop to a My Cloud via WiFi. The device can be on the other side of your home or even thousands of miles away, thanks to the Internet. In my experience, this technology works well for backups, as fast interactive speed isn't needed, and large quantities of data don't need to be transferred immediately, but rather, the data can be transferred over many hours.