Apple’s Big Sur operating system came out six months ago, but I only got around to installing it on my 15″ Macbook Pro (500G storage, 8GB memory) two or three days ago. Except the installation stalled or got gummed up, so I had to run down to Best Buy for a 2 terabyte Western Digital external hard drive. I loaded the entire contents of the Mac onto the WD, wiped the Mac clean and re-installed everything — now it’s all good.
I haven’t owned an external hard drive since ’08. It only held 500G, weighed a couple of pounds and needed a wall plug-in for power. The WD is (a) powered by the laptop, (b) only a little bit bigger than a playing card and (c) barely weighs anything.