What obsolete knowledge do you know by heart, and would like to share?

Along these lines, I have several important memory locations memorized. POKE 53280 and 1 to change the border and background colors. 828 is the cassette buffer, and 49152 the free memory above BASIC ROM. SYS 64738 resets the machine.

I also can recite the powers of 2 up to 65536.

Fun fact: There's a common misconception that this would load the first program on a disk, but it actually loads the most recently loaded program from the disk. If the disk is detected as being freshly inserted (as determined by the 2-character identifier in the disk's directory header), that defaulted to the first program in the disk's directory.

Admittedly, most of the time that makes it a distinction without a difference, but if you'd loaded something else from the same disk first, and you then wanted to load the first in the directory, you would need to use LOAD":*",8,1 instead.

That extra colon is vaguely related to the colon in C:\ on Windows computers. A lone colon was taken as an abbreviation of 0:, because in Commodore DOS(es) the drive "letters" were numbers. Dual slot drives were possible and then the two slots were 0: and 1:.

"So what's the 8 for in the LOAD command?" you might ask; "Isn't that the drive "letter" "? No, that's the device number. Note that drives on the 8-bit Commodores were always external. The 8 was more like the drive's "IP address" on the serial bus.

"What about the ,1?" That meant to LOAD the program at the memory address specified by the program's header on the disk. Without that, the computer would ignore the header and try to load into BASIC memory.

The neat part about loading at any address meant that it could overwrite parts of zero-page where the computer kept pointers to important internal functions. Overwrite the right one of those and the computer could be convinced to jump to a routine in the program that had just loaded without the user needing to type RUN.

So, if you wanted to be i) certain of loading the first program in the directory of ii) the disk in the second slot of iii) a dual-slot drive on the serial bus identifying as device/address 9, and then iv) have the program load at its preferred memory location, you'd need to use LOAD"1:*",9,1

The number of people who found the need to type that command in earnest, even back in the heyday of Commodore, probably numbers in the low tens, but there it is.

How's that for an obscure info dump?

I choose to believe that the * means everything... but what does the 8,1 signify?