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On this day in 1975, Steve "Woz" Wozniak tested the prototype of what would become the Apple-1 computer. Here are 10 fascinating facts about that history-making machine.

Edit: Though we all thought June 29 was a big day in Apple history, it turns out even the man himself got it wrong. Steve Wozniak told CNET, "I had gone back to old old materials to figure out that June 29 date but it was actually quite wrong. The incident was reported correctly by me but it occurred some time later in the year. Kind of a bummer sort of mistake but the importance was there on the day it actually happened." Thanks, Woz!

1. Woz designed the very first Apple-1 computer prototype based on the $175 Motorola 6800 CPU. When a team of former Motorola engineers released the $25 MOS 6502 CPU, Woz adapted his system around the cheaper chip to make the Apple-1 more affordable.

2. The processor ran at just 1.023 MHz. Its 4KB of RAM was expandable to 8KB or 48KB. An additional cassette tape interface allowed the user to save program data. This was one of the precursors to the floppy disc.

3. The Apple-1 computer consisted of a single motherboard, with about 60 chips, fully pre-assembled. At the time, computers did not come assembled, and consisted of multiple circuit boards.

4. Even though it came with a pre-assembled motherboard, that's all the Apple-1 came with. Owners had to make their own case.

5. Woz included motherboard support for CRT TV compatibility -- a novel idea at the time -- as well as support for a keyboard and a power supply (all of which the user needed to supply themselves).

6. Woz offered the Apple-1 design to his current employer, Hewlett-Packard, five times. HP turned him down.

7. A Star Trek game was released for the Apple-1 on a cassette in 1977 for $5.

8. Steve Jobs was the one who convinced Woz to try and sell his computer. Woz built 200 units by hand, and all but 25 of those units sold during the short time the Apple-1 remained on the market.

9. The wholesale price of the computer was $500. The retail price was the eyecatching $666.66. According to Woz, "I was into repeating digits...Steve worked a deal to sell his computers wholesale price to the store for $500 bucks. What should the retail be? Add a third on. That puts it at about 667 plus its 666.66 because it's all one digit, to me that's just an easier way to type. We didn't know the number had religious significance." These days, Apple-1s occasionally pop up at auction. The most an Apple-1 ever sold for was $905,000 for a working unit in 2014.

10. As of June 2015, only 66 Apple-1s remained in existence according to an online Apple-1 registry. Woz was the only one at the fledgling Apple who could provide tech support for the Apple-1, so users were encouraged to trade their units in for the Apple II when it was released in 1977 and many of the original Apple I units were destroyed.