Comment by MisterTea
I always get reminded of this when I see all the weird praise the 555 gets: https://www.electronicdesign.com/technologies/analog/article...
It's one of those poor/early designs like the 741 opamp that has since been superseded by much better chip designs but is thoroughly ingrained in hobbyist and EE101 classes to the point where people think it must be a good design because it's so venerated. It's meme driven really.
However, for educational and hobby use, eh whatever. If I was a professor and the curriculum called for 555 or 741 use I would thoroughly state to the students that A. these devices are historic and good teaching tools, however, in the real world their performance has been surpassed and you would use new designs. Maybe even present a few alternatives like the TL081 and what Pease mentioned for timing.
The TL081 family of op amps is definitely in the "old parts you should (sometimes) use" category (for price/performance) but there have been much better op amps for not much more money for a long time now. Both the now-ancient 2nd edition and the aging 3rd edition of Horowitz and Hill recommend the LF411 for a JFET-input general purpose jellybean, for example.
For learning you some analog, I would recommend the LM358 op amp and the LM393 comparator and all the old National material on them. The LM358 has its quirks so you won't think op amps are ideal but you still see them in a ton of stuff, because they're dirt cheap and adequate for a lot of things, and the LM393 comparator is still so good you really should know why you're choosing anything else - micropower or exotically high speeds or whatever.