If you were ever interested in the early days of PHP (back in the PHP/FI days, pre-3.0 even) Rasmus Lerdorf has a post sharing an old Changelog he created for some of the first PHP version releases.
Ran across this Changelog from a long long time ago. Read from the bottom up. I added the PHP Tools lines at the bottom for context. So many early decisions made on a whim still affecting us today. And then there are things like "Removed **, // and %% operators" which did a vector dot-product and its inverse, I think. I seem to recall deleting it when I tried to document it.
No years on most of the entries, but version 1.90 was on Sept.18, 1995.
It's an interesting read to see some of the thoughts and additions to the language early on. You can see which functions were added way back then and which ones have been dropped since including an entry for October 17th - "First public release of the code".