There is one mysterious thing about the Apple-1, which was the first computer made by Apple. Namely the serial number written by hand on some of these computer units.
Called mysterious because the serial number was handwritten, and (at first) no one claimed to have written the number. Steve Wozniak and Steve Jobs both admitted that they did not know how this number could appear on the Apple-1 mainboard.
So did Daniel Kottke, who assembled and tested several of the Apple-1's mainboards. Paul Terrell, the owner of the Byte Shop who bought 50 units of the Apple-1, admitted that he did not know the existence of the number.
But the mystery was finally solved by Achim Baque, the man who recorded the Apple-1 Registry -- a list of all Apple-1 computers. Although at first, this is not an easy thing.
If you look closely, the writing of the serial number is very similar to the writing of Steve Jobs, even though Jobs admitted that he did not write the number. But to be sure, Baque looked to a world-famous date-writing service to compare the serial number writing with Jobs' handwriting.
Unfortunately, Jobs is known to rarely write his signature, which makes Jobs' signature very valuable. Baque then found a sample of Jobs' handwriting and gave it to the handwriting recognition service provider.
Unfortunately, the sample photo of Jobs' handwriting was deemed insufficient because the analysis had to be carried out by examining the writing directly on the mainboard. He then took two Apple-1 mainboards for research, along with a postcard that Kottke had sent in Jobs' handwriting.
After three months of analysis of Jobs' photographs and handwriting, the mystery was finally solved. The handwriting on the Apple-1 mainboard is identical to Jobs' handwriting.