Checksum Algorithm

I see a new article by Grim! Thanks!

Just a few questions:
- Only the first listing is credited. Are all the others from the same author, or from Grim?
- I know it should be easy to find, but maybe a few links about HOW to calculate the hashes? I'm pretty sure there are thousands of CLI tools that do that, but one link would be enough.
- Is there a "collision" rate that could be put in the table with each algorithm? One would be tempted to use the fastest!
- Maybe a small conclusion, for beginners, about how to get a CRC from a file, and compare the result? How is encoded the 32 bits result (is HL the Most Significant Word?)?

One again a very interesting article. But like often, without a full context, a lot of people will be bummed by it and miss an opportunity to learn something that could be useful.

Ah, an interesting addition would be about how to create such CRC in Z80 (maybe not all, but at least one).
For example, in Orion Prime, I did a little checksum check in the save games to be sure no one tampered with its bytes for cheating (actually, it was only a special encoding using a seed written in the first bytes as a decoder, but the goal was the same).
So a CRC, even simple, to make sure data generated on a CPC are not modified, would be useful.