I don’t know about you, but I’d be absolutely lost without my MacBook Air. The laptop is so light that I forget that it’s in my bag most of the time. Within seconds, I can have the thing out on my lap, tethered to my phone, and can hit up the Interwebs at will. That’s portability.

What did the first commercially available portable computer have going for it? Well, it was super light at a whopping 55 pounds. It also cost $19,975, more than some cars do these days.

Take a quick gander, then I’ll tell you about what this baby had inside:

Yep, that’s a “laptop”. Kind of. Here’s the full details on the IBM Portable PC, model number 5100:

First introduced: September, 1975

CPU: IBM proprietary, 1.9MHz

RAM: 16K, 64K max

Display: 5″ monochrome monitor 64 X 16 text

Storage: Internal 200K tape (DC300)

Ports: tape / printer I/O port

OS: APL and/or BASIC

When you check out the Wikipedia page for the IBM 5100, here’s what it says:

A single integrated unit provided the keyboard, five-inch CRT display, tape drive, processor, several hundred kilobytes of read only memory containing system software, and up to 64 KB of random access memory. It was the size of a small suitcase, weighed about 55 lb (25 kg), and could be transported in an optional carrying case, hence the “portable” designation.

So it was the size of a small suitcase? Yeah, how’s that for portable? If you ever find yourself complaining about how clunky and big your gadgets are, remember this guy lugging around the $20k “ultra portable” IBM 5100:

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