2015 MacbookPro External Hard Drive?

It is not that old!

This is the external I use with my 2012 MacBook Pro. It has provided excellent performance and reliability:

https://eshop.macsales.com/shop/owc-mercury-elite-pro-mini

This, from the same company, is a bit less money and still reliable. My daughter has been running one for over seven years on two different Macs.

https://eshop.macsales.com/shop/owc-mercury-on-the-go-pro/usb-3.1

I moved to these are having nothing but trouble with "name brand' drives that go on sale every other weekend. Since moving to OWC external drives, I have had zero issues.

hermz09 Said:

"2015 MacbookPro External Hard Drive?[...]Here is what I know about my computer. If anyone could help and explain this as if you were explaining it to a small child (who has perhaps never seen a computer before) I'd really appreciate it![...]"

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Well, IMO based on your specs, I wouldn't say it is oh-so old to be considered obsolete. But, here are the specs defined (in-brief):

• MacBook Pro (Retina, 15-inch, Mid 2015) - not a shiny display - 15" is measured diagonally - and runs Catalina (latest macOS to date, as of this reply)

• 2.2 GHz Intel Core i7 - Quad Core Processor - great for Multitasking (running many apps simultaneously, such as TV app and Music app)

• 16 GB 1600 MHz DDR3 - 16GB RAM (Random Access Memory) is high-end and is beneficial for multitasking (as presses are made, RAM places it aside, so you can perform more processes).

• Running Mojave 10.14.6 - is 64-bit-compatible, meaning it will run only 64-bit app from then on out - so you would have to upgrade your apps to the 64bit-only option, by contacting the developer for the correct driver of a 64-bit app.

Your computer specs are really somewhat irrelevant when buying an external drive except for connection ports. What you need to do is to erase and format the external Mac OS Extended and GUID partition scheme once you plug it into your computer via USB because a lot of them are pre-formatted for Windows. And, an external does not need any software to work.

Literally any external USB hard disk drive will work.

If you don't know where to start, https://eshop.macsales.com/shop/external-storage#interface-ports:usb-3-0-usb-3-1-gen-1